This is mainly for if you've done something silly like trying to clone a Live, running VM image. In this example, the VM initially finds grub and tries to boot but is kicked straight into initramfs rescue mode/busybox right after this.
If you've done this "silly" thing, you could have dataloss but a lot of times just using fsck will fix it as you are guaranteed at best to have some corruption and inconsistencies in the filesystem. My theory is that some files wer........
This guide assumes you have a working Postfix server and want it to sign with DKIM.
There are a few things we have to understand to make all of this work though, which require you to be familiar with DNS as well.
1.) Install OpenDKIM
apt install opendkim
systemctl enable opendkim
2.) Edit /etc/opendkim.conf
Syslog yes
SyslogSuccess yes
Mode&nbs........
apt install tftpd-hpa
#change TFTP_ADDRESS to by setting address to 192.168.1.1:69 or the IP you need, otherwise it will listen on all IPs and interfaces which could be a security risk.
# edit /etc/default/tftpd-hpa
TFTP_USERNAME="tftp"
TFTP_DIRECTORY="/srv/tftp"
TFTP_ADDRESS="192.168.1.1:69"
TFTP_OPTIONS="--secure"........
This sometimes happens when trying to install the EFIversion of grub to a device when you are booted into Legacy/MBR mode. It doesn't seem to occur on all machines, but some and seems somewhat BIOS dependent.
grub-install --target=x86_64-efi /dev/sda
Installing for x86_64-efi platform.
grub-install.real: warning: Couldn't find physical volume `(null)'. Some modules may be missing from core image..
grub-install.real: warning: Couldn't find physica........
sysctl vm.overcommit_memory=1
echo never > /sys/kernel/mm/transparent_hugepage/enabled
echo 511 > /proc/sys/net/core/somaxconn
1:M 26 Nov 2023 21:34:33.840 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.
1:M 26 Nov 2023 21:34:33.840 # Server initialized
1:M 26 Nov 2023 21:34:33.840 # WARNING overcommit_memory is set to 0! Background sa........
This seems to happen in many different drivers but it happened more often in newer versions such as 530 vs 525.
Then nvidia-modeset goes to 100%
There are many reports of this appearing since driver 4.70 and I can confirm I've seen this in various machines.
https://forums.de........
Have you got this error from Apache?
[notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[error] (28)No space left on device: Cannot create SSLMutex
At first glance it appears that you may be out of disk space but the issue is ipc or interprocess communication.
This will clear out the ipcs processes so things can work, this often happens during high traffic and may be a sign of DDOS.
The command below will fix it, it will list al........
Have you ever tried mounting a partition that you exists but you get this error?
mount: /mnt: can't read superblock on /dev/sda1.
The superblock in this example was bad because the physical disk had corruption and bad blocks/sectors. However, the data was generally accessible and you can always try this trick below (with caution and no warranty).
This is specifically for filesystems that place superblocks in multiple locations, which........
Nov 15 17:00:49 rttbox kernel: overlayfs: filesystem on '/var/lib/docker/overlay2/check-overlayfs-support450709549/upper' not supported as upperdir
Nov 15 17:00:49 rttbox dockerd[93755]: failed to start daemon: error initializing graphdriver: driver not supported
The above error is often/normally caused because you are trying to run docker out of an unsuitable directory/filesystem. For example if you try to place docker's data inside an existing overl........
This is a weird issue as sometimes when upgrading or even migrating, this could happen and the reason is simple but maybe not 100% obvious at first.
You will find that your GUIdoesn't load and most services fail to start, even logind
Here are some errors you may see:
Mar 13 22:22:23 rttbox systemd-logind[2892]: Failed to connect to system bus: No such file or directory
Mar 13 22:22:23 rttbox systemd-logind........
Is python3-pip pip3 not working anymore?
Traceback (most recent call last):
File "/usr/bin/pip3", line 11, in
sys.exit(main())
File "/usr/local/lib/python3.5/dist-packages/pip/__init__.py", line 11, in main
from pip._internal.utils.entrypoints import _wrapper
File "/usr/local/lib/python3.5/dist-packages/pip/_interna........
A lot of companies are unsure which solution to choose and many may not be aware of Docker Swarm as an alternative to Kubernetes. One thing that many Sysadmins find is that Docker Swarm is simply easier, quicker to setup and maintain by far than Kubernetes.........
In today’s digital landscape, finding a reliable and secure Virtual Private Server (VPS) or Virtual Dedicated Server (VDS) goes beyond just comparing specs and prices. With increasing concerns over data privacy, security breaches, and government surveillance, the wisdom of choosing your VPS/VDS provider based on juri........
This will be the goto to help solve e-mail delivery issues and talk about many practical issues that happen between developers, admins and scripts that send e-mail and do things that may not be acceptable or cause deliverability problems.
Sendmail Stuff
Edit /etc/mail/sendmail.mc
The problem is that if you send directly out from the server using the mail function, the Return-path of the e-mails will be username@thehostnameoftheserver.com. Let........
This is for the situation that you're doing other things that may conflict or have your own custom rules and ufw keeps overriding iptables.
A lot of guides don't work, and even ufw reset does not work, because it still leaves the old ufw chains.
Here is what works to disable ufw completely
systemctl stop ufw
systemctl disable ufw
ufw disable
rm -f /et........
You are probably using some custom image or maybe this is some sort of container that didn't boot with systemd.
The solution is to use "reboot -f"
reboot -f
This will force the system/OS/VM/container to reboot.........
find /usr/share/zoneinfo/|sed s#"/usr/share/zoneinfo/"##g|grep "/"|grep -v posix|grep -v ^"Etc/"|grep -v ^right|grep -v ^"SystemV"
Africa/Addis_Ababa
Africa/Abidjan
Africa/Blantyre
Africa/Lusaka
Africa/Casablanca
Africa/Libreville
Africa/Asmara
Africa/Bujumbura
Africa/Dakar
Africa/Lagos
Africa/Malabo
Africa/Harare
Africa/Kigali........
Step 1.) Upgrade to Debian 11 first
The process to go to Debian 12 is not as smooth as 11, when trying to upgrade from Debian 10. In fact, it doesn't work directly, so you'll first need to follow this guide to update to Debian 11, reboot and come back here if successful.
Step 2.) Update sources.list
Update your /etc/apt/sources.list like this:
deb http://........
If you get this error, it is often because you have configured Apache with modules that weren't actually installed. Eg. you try to load the PHPmodule but didn't actually install the apache2 php module, so the server can't start. In general, this error can often be caused by issues with problematic modules and/or Apache being configured for modules that have not actually be installed (eg. libapache2-mod-php) is missing.
The above results in this less than obv........
This should work for most console ports of other manufacturers too. It is a quick and simple method for emegencies or deploying a few appliances/devices in a non-standard environment or small environment.
However, if this is a route thing, or the equipment is not physically close to you, it would be best to use some sort of "Terminal" server which is an IP connected switch with several serial ports built-in for this purpose. Normally they accessible by web/........
The issue is that Docker images are stripped down, so many tools and even python3 is missing, so you'll have to build or update the actual image yourself.
I assume you have started an image with something like this and that you have the Nvidia Toolkit installed (assuming you are using GPUs). If you're not using nvidia just remove --runtime=nvidia --gpus all.
docker run -it --runtime=nvidia --gpus all ubuntu bash
These works for most images li........
You'll notice that /etc/resolv.conf contains dire warners on most Linux Desktops.
# This file is managed by man:systemd-resolved(8). Do not edit.
#
# This is a dynamic resolv.conf file for connecting local clients to the
# internal DNS stub resolver of systemd-resolved. This file lists all
# configured search domains.
#
# Run "resolvectl status" to see details about the uplink DNS servers
# currently in use........
This does not seem to be officially documented but makes sense that an overlay on an overlay does not work and is considered an unsupported filesystem as is even NTFS . Some admins/organizations try to use ecyptfs as a simple solution to encrypt the contents of Docker. Instead, you could probably........
Let's say you have a directory /mnt/raid which has files and directories inside it, but nothing is mounted to it.
Then you mount a block device such as /dev/sdh to /mnt/raid
Even though /mnt/raid has files and directories there, you can only see the mounted contents of /mnt/raid.
How do we access the original contents?
Just do a bind mount of the root filesystem to another location.
mkdir /bindmount
mount --bind / /b........
The issue is when you need to echo something as root/sudo, that it doesn't work. You can never do a sudo echo to an output file as you'd expect.
Take an example to clear out wasted RAM buffers/cache like this:
sudo echo 1 > /proc/sys/vm/drop_caches
-bash: /proc/sys/vm/drop_caches: Permission denied
The solution is to run tee as sudo/root
What we do is echo 1, but then pipe it to the "tee" command as sudo........
So you started a process or other important task that is remote but it is in the foreground and on a pts. This means if you background with Ctrl + Z or otherwise logout or get disconnected that the process will be stopped.
Here is how you can solve the problem:
1.) Hit Ctrl + Z to suspend the process.
2.) Type bg to restore the process into the background. If you do a ps aux on the process you will see it was restored with the & at the end, which puts........
We could always disable swap but this would normally be a bad idea unless you have an incredible amount of RAM and a workload that will never exceed it. However, for live/containerized and high performance environments it could be desirable.
Another middle ground may be to set swappiness to a lower number.
You may also want to clear your kernel's cache, which could be eating up RAM unnecessarily by c........
A lot of developers want to go to 3.11 because of the speed improvements, but most distros never have the latest Python version.
Using the deadsnakes third party repo is the easiest way aside from compiling it yourself (which is safer and recommended):
Step 1 - Add the repo
apt-add-repository ppa:deadsnakes/ppa
If you get an error about requests then install it:........
This sort of thing normally happens your python3 or pip3 has been updated, because you have to in order to use pip, but the newer pip now breaks compatibility with your old python (3.5 in this case).
There are a few solutions, the easiest is perhaps to upgrade to a newer OS with a newer distro provided Python 3 or to manually install a newer version of Python/OR use a PPA like deadsnakes that provides newer versions.
........
haproxy is one of the best known and widely used Open Source load balancers out there and a strong competitor to nginx.
haproxy is used by many large sites per Wikipedia:
HAProxy is used by a number of high-profile websites including GoDaddy, GitHub,........
Be very careful about what filename you specify in dhcpd.conf if you get an error like this:
NBP filesize is 0 Bytes PXE-E23:Client received TFTP error from server.
If you specify "BOOTx64.efi" then the file had better not be called "BOOTx64.EFI" as it is case sensitive. It's really a case of th........
Virtualbox is a very powerful tool, but for some use cases it is less than optimal.
Say you are in a work, lab or other environment where you are not alone on the physical network and there could be overlap of IPs, but you need all of your VMs to be contactable from your host, VMs need to communicate with each other, and VMs need internet.
NAT Network will give you VM to VM communication and internet, however, it is buggy and unstable. It also doesn't allow host to VM co........
In this example we install debian 10 with --variant=minbase which gives us a minimal/tiny install. Don't use variant if you want the full size install.
mkdir /tmp/deb10files
debootstrap --variant=minbase buster /tmp/deb10files/
Did you get an error?
debootstrap --variant=minbase buster /home/theuser/VMs/deb10files/
You'll get this error if you make a directory in your home........
You can read lots of posts about this issue but there is not much information about why this is the case or how grub determines the root= device name. Some even suggest modifying grub.cfg manually which is a disaster as the next kernel update will cause grub to revert back to the device name.
For most people this won't be an issue but those using template system, automated deployments and working in embedded may run into this issue with custom embedded and created minimal kernel........
Here is an easy way to restore things if you have the starting point and size of each partition using fdisk:
In this example we pretend that /dev/sda was wiped out, but the running system still has the info in /sys/class/block/sda
Go into each partition and record the "start" and "size"
hostdev@box /sys/class/block/sda/sda1 $ cat start
2048
hostdev@box /sys/class/block/sda/sd........
Remember that control connections are established on port 1723 and then actual data is transferred over GRE protocol 47.
If you have a NAT setup this will work without special forwarding or accepting of GRE packets (normally if you are not blocking outgoing connections and accepting established and related connections).
The below two commands will get things going so PPTP and GRE work
We first load the ip_nat_pptp module which allows PPTP to work with........
So say you happen to have 2 NICs of the exact same chipset, they will generally show up as the same name, with possibly a different revision in lspci. Normally this is not an issue if you have a server with 4 NICs, generally the eth0 to eth3 appears from left to the right (or right to left on some vendors) so it doesn't take much figuring out.
Generally if you have different chipsets for different NICs, it should be easy to know which one is eth0 or the first NIC in the OS.........
Sometimes due to your BIOS/EFI you may find that you have chosen "Energy Efficient" for your CPU which may effectively disable turbo mode. This is because "Energy Efficient" will often restrict or throttle your CPU to the base speed. This can impact nearly any CPU such as Intel's, AMDs, Opteron, Xeon etc...
This is of course frustrating, for example if you have a CPU that is 2.0GHz base speed but turbo to 2.5GHz, you will never hit more than 2GHz.........
It sounds intuitive that you may just move the /var/lib/docker dir to another location and symlink it back but it won't work and you'll get an error.
How to move Docker Storage the Correct Way
This assumes that you want to use /mnt/raid as the new location.
1.) Stop Docker
systemctl stop docker
2.) Move /var/lib/docker
mv /var/lib/docker /mnt/raid/
3.) Edit the Docker daemon file
Specify the path you wan........
Solution for python pip3 not working anymore
from pip._internal.cli.main import main
File "/usr/local/lib/python3.5/dist-packages/pip/_internal/cli/main.py", line 60
sys.stderr.write(f"ERROR: {exc}")
wget https://bootstrap.pypa.io/pip/3.5/get-pip.py
python3 get-pip.py
DEPRECATION: Python 3.5 reached the end of its life on September 13th, 20........
1.) Make sure your conf register is 0x2102
Do show version and at the very end of the output you will see the Configuration register.
show version
Configuration register is 0x2102
If the config register is not 0x2102 then enter this command:
r1#configure terminal
r1(config)#config-register 0x2102
r1(config)#end
2.) Let's Erase the NVRAM/flash........
If you are getting this error from systemctl "Loaded: masked (Reason: Unit hostapd.service is masked.)" we need to unmask the service.
Solution
systemctl unmask hostapd
Removed /etc/systemd/system/hostapd.service.
It's fixed
root@routerOS:/var/log# systemctl start hostapd
root@routerOS:/var/log# systemctl status hostapd
● hostapd.service - Access point and authentication server for Wi-Fi and Ethern........
In this scenario, let's say you want to clone your OS at the filesystem level and the source system (the system you want to clone from) is in use.
Doing a blind rsync / is a big problem because it uses twice as much space for no reason.
The reason for this is that with ecryptfs you have a /home/.ecryptfs directory which has the actual encrypted versions of your files and folders. However your home directory (eg. /home/someuser) is mounted.
Doing the blind rsync will ca........
It may appear to be an Xorg or lightdm/gdm/mdm error but in reality for many users with this issue, it's a driver conflict and issue. I had a system that had two GPUs, an Intel and Nvidia GPU.
The only thing that got it working was to remove the nouveau driver and blacklist it so it never came back, then the Intel GPU works fine without these issues.
Solution
sudo rmmod nouveau
add nouveau/other driver to blacklist
edit th........
NetworkManager is normally good for GUI users who may not be good with manually confguring devices, but if you are using things like bridging and bonding, it will often break things.
How To Disable NetworkManager
systemctl disable NetworkManager
Now that it's disabled you will need to stop NetworkManager. NetworkManager will still be running until you reboot next or manually stop it.
How To Stop NetworkManager
systemctl stop........
I've encountered this after upgrading some Debian/Ubuntu/Mint based systems for no explicable reason, although there are some bug trackers on Ubuntu that document this: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1889509
The short end of the solution is that you need to properly reinstall grub.
1.) Boot from a LiveCD
2.) Mount your root / filesystem and don't forget to mo........
Is your /var/log/journal overweight and bloated? For example a decent install of Debian 11 with most applications and services ends up being about 4.9G with the journal taking a few gigs.
du -hs /var/log/journal/
1.3G /var/log/journal/
By default in a lot of distributions there is no maximum size so it will keep growing. This is especially problematic for embedded distributions and devices, but is also a huge waste of sp........
Sometimes manual intervention on various Linux system's, including Debian, is required to fix things after waking up from sleep.
One persistent issue is the sound system / pulseaudio needing to be reset and not working until you do that after waking up. It's not clear if it's an OS issue itself or the sound driver, but this will fix things.
Where do we put scripts or commands that need to be used upon wakeup automatically?
/lib/systemd/syst........
This error implies that there may be an issue with Xorg or maybe your NVIDIA GPU cannot start or initialize:
35 laptop kernel: [ 2031.857704] nvidia: loading out-of-tree module taints kernel.
35 laptop kernel: [ 2031.857724] nvidia: module license 'NVIDIA' taints kernel.
35 laptop kernel: [ 2031.857725] Disabling lock debugging due to kernel taint
35 laptop kernel: [ 2031.873280] nvidia: module verification failed: signature a........
Bonding is an excellent way to get both increased redundancy and throughput. It is similar to the "Network Teaming" feature in Windows.
There are a few different modes but we will use mode 6, I think it's the best of both worlds, as it is not just a failover, but it provides round robin, so you will get redundancy and load balancing. So if you have a 1G single port, you will have a combined throughput of 4G at this point. Just bear in mind that the true thr........
If you are using mint, delete the preference that stops snap from installing (as it is required for lxc)
sudo rm /etc/apt/preferences.d/nosnap.pref
1. Install lxd:
sudo apt install lxd
Issues install lxd or errors? Click here
Debian at this time does not have lxd so you'll need to use snap:
sudo apt in........
This can be used on almost anything, since Gluster is a userspace tool, based on FUSE. This means that all Gluster appears as to any application is just a directory.
Applications don't need specific support for Gluster, so long as you can tell the application to use a certain directory for storage.
One application can be for redundant and scaled storage, including for within Docker and Kubernetes, LXC, Proxmox, OpenStack, etc or just your image/web/video files or even da........
If your audio is not working and you got this in your syslog:
pulseaudio[13710]: [pulseaudio] sink-input.c: Failed to create sink input: too many inputs per sink.
The issue is generally caused by too many audio inputs, or in other words you have too many applications that are hooked into pulseaudio.
An easy and notorious offender is by having dozens of Firefox browser tabs open.
Solution:
Close all of your Firefox and the problem will........
This happens during an apt update and is related to an issue with sources.list, which is particularly troubling, if you are doing a "live-build".
P: Configuring file /etc/apt/sources.list
Hit:1 http://deb.debian.org/debian bullseye InRelease
Get:2 http://deb.debian.org/debian bullseye-updates InRelease [39.4 kB........
(firefox:9562): LIBDBUSMENU-GLIB-WARNING **: Unable to get session bus: Failed to execute child process "dbus-launch" (No such file or directory)
ExceptionHandler::GenerateDump cloned child 9743
ExceptionHandler::WaitForContinueSignal waiting for continue signal...
ExceptionHandler::SendContinueSignalToChild sent continue signal to child
[Parent 9562, Gecko_IOThread] WARNING: pipe error (40): Connection reset by peer: file /build/firefox-EymEXX/fire........
The Best Docker Tutorial for Beginners
We quickly explain the basic Docker concepts and show you how to do the most common tasks from starting your first container, to making custom images, a Docker Swarm Cluster Tutorial, docker compose and Docker buildfiles.........
Just click on the Start Menu and go to "Startup Applications"
Then click on the "Add"Button
Now enter the command we need to open the folder/directory automatically using the filemanager
For remote SSH host (you need pub key auth for it to open without a pa........
Why choose OpenVPN instead of a firewall appliance?
OpenVPN can be a reliable and easy replacement for traditional hardware or just be an additional tool that your company uses so that the firewall can focus on its job rather than acting as a VPNappliance at the same time.
When comparing OpenVPN with traditional firewal........
In our 2024 VPS Server/Cloud Buyer's Guide, we place the location of your VPS/hosting/server as one of the priorities that is often overlooked.
2024 Update - Datacent........
You might assume you have a bad drive or the SATA interface/cable is bad, or the power supply is bad/weak to the drive. These are all possible issues, but definitely check your SATA cable for "twisting". It is a big issue because until the error stops or times out, your system will not boot (in my case this was the case even though the drive with the issue was not part of the OS or booting process at all).
If you run an open rig that you move around often that ha........
How To Install Wazuh Server / Quickest Installation
Wazuh (forked from the well known OSSEC project) is a full SIEM (Security Information Event Management) that works extremely well with the platforms it natively supports as an "Agent", which allows you to do scans of everything such as all processes running, CVE vulnerability check, incident reporting etc...
Prerequisites:
A lot of issues with Wazuh seem to be caused by i........
A lot of newer installs will automatically prohibit the root user from logging in directly, for security reasons or they will only allow key based access.
If you know what you are doing/don't care about security or have an incredibly secure password for testing, then you can enable it.
Edit this file: /etc/ssh/sshd_config
Find the following line: PermitRootLogin
Set it like this:
PermitRootLogin yes
Now rest........
1. Let's work from an environment where we can install Ansible on.
If you are using an older version of Linux based on Mint 18 or Ubuntu 16, you may want to get the PPA and get the latest version of Ansible that way:
sudo apt install gpg
sudo add-apt-repository ppa:ansible/ansible
sudo apt update........
There are many reasons why Proxmox services may not start, but one common one, is if you have changed your /etc/hostname or /etc/hosts and don't have a valid FQDN (eg. proxmox01 instead proxmox01.com).
Failed to start The Proxmox VE cluster filesystem.
Failed to start Proxmox VE firewall.
Failed to start PVE Status Daemon.
Failed to start Proxmox VE scheduler.
Failed to start PVE Cluster HA Resource Manager Daemon.
Failed to star........
From the terminal do this:
cat /proc/cpuinfo|grep -E "svm|vmx"
You should get output like this(svm = AMD-v and vmx=Intel-VTx):
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqd........
The Linux Mint team has disabled it by setting an apt preference, you can edit or just remove the file:
sudo apt install snapd
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package snapd is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source........
There aren't too many simple guides that show you how to use commands to setup your USB or other drive as a normal bootable drive where you can easily boot custom kernels or whatever OS you would like.
1. Get the tools we need:
We install "syslinux" for MBR and "syslinux-efi" for EFI and "MBR" as we need a tool that embeds the actual MBR into our USB:
sudo apt install syslinux syslinux-efi mbr........
This was done on a 2900 but applies to all the switches of the same era.
Step 1 - Power Cycle and enter recovery mode
If you have physical access you can power cycle and hold the mode button down for 15 seconds. After that the SYS light will flash on the switch and you will see the following screenshot.
If you don't have physical access (eg. it is a datacenter swich over console only) then power cycle and hit "Ctrl+Pause/B........
Usually if you get the grub boot loader and it doesn't show any boot options, it's because grub was not installed correctly and/or the partition that it is supposed to be on has changed or does not exist. It can also happen if you install Linux to one drive, but the boot loader to another by accident, whether EFI or MBR/Legacy mode.
You can normally fix your booting/bootloader/MBR/EFI it by chrooting into your root partition:
#become root
sudo su........
Enable "cli" mode equivalent in JunOS
cli
Configure Mode
configure
So rather than going to the console on a Cisco switch and typing "enable" and then "conf t", the equivalent in JunOS is "cli" and "configure".
How Do You Apply Changes You've Made?
You can make all kinds of changes to the switch, but remember they are not........
Many people may not be aware that you can turn commodity hardware into a Mikrotik OS and there are various options which is "CHR" (Cloud Hosted Router) which is a VMimage meant for Virtualization only (seriously, I've tried to dd the image to a physical server and it just crashed as it does not contain any drivers for physical).
One note as well if you are trying to do a baremetal install you may get an error "Error Loading Operating System" or........
The problem seems to be that whatever kernel and initrd you have is tied to an old version of CentOS 7 that is no longer in the current repos of most mirrors.
If you were previously able to PXEboot and install CentOS and you are sure your network and tftp are good the problem is that you have an outdated kernel and initramfs that point to a defunct version.........
It really seems limited in that it can mainly give you the things you would see on the physical unit such as load etc..
wget https://downloads.sourceforge.net/project/apcupsd/apcupsd%20-%20Stable/3.14.14/apcupsd-3.14.14.tar.gz?r=https%3A%2F%2Fsourceforge.net%2Fprojects%2Fapcupsd%2Ffiles%2Flatest%2Fdownload&ts=1598115866
tar -zxvf apcupsd-3.14.14.tar.gz
cd apcupsd-3.14.14
[root@somebox apcupsd-3.14.14]#
./conf........
Is a mdadm check on your trusty software RAID array happening at the worst time and slowing down your server or NAS?
cat /proc/mdstat
Personalities : [raid1] [raid10]
md127 : active raid10 sdb4[0] sda4[1]
897500672 blocks super 1.2 2 near-copies [2/2] [UU]
[==========>..........] check = 50.4% (452485504/897500672) finish=15500.3min speed=478K/sec
........
apt install software-properties-common
add-apt-repository ppa:deadsnakes/ppa
apt update
apt install python3-pip
apt install python3.7 curl gnupg python3.7-dev git
ln -s /usr/bin/python3.7 /usr/bin/python3
pip3 install numpy keras_preprocessing
curl https://bazel.build/bazel-release.pub.gpg | sudo apt-key add -
echo "deb [arch=amd64] http://storage.googleapis.com/bazel-apt stable jdk1.8" | sudo tee /etc/apt/sources.list.d/bazel........
Most newer distros inexplicably cause your NIC to have what Icall "random" non-standard name conventions because of systemd.
This is a big problem for many people and especially those running servers. Imagine that you have a static IPconfigured for ens33 but then the hard disk is moved to a newer system, the NIC could be anything from ens33 to enp0s1, meaning that manual intervention is required to go and update the NIC config file (eg. /etc/network/interfa........
I used to believe that for Desktops especially that the "ondemand" CPUfrequency changing that kernels included with Ubuntu and Debian based distros have would be sufficient for snappy performance.
However, you can feel the lack of performance on the fastest computer if you have ondemand. A lot of times even under high load 100% of your CPUfrequency in MHz will not be used.
For example a 2.8Ghz CPUmay only run at 1.8MHz or even .9GHz. Now........
yum -y install wget unzip
wget https://download.nextcloud.com/server/releases/nextcloud-18.0.2.zip
unzip nextcloud-18.0.2.zip
yum -y install php php-mysqlnd php-json php-zip php-dom php-xml php-libxml php-mbstring php-gd mysql mysql-server
Last metadata expiration check: 0:58:02 ago on Fri 13 Mar 2020 02:12:49 PM EDT.
Dependencies resolved.
===================================================================........
unable to connect to camera. Camera has been disabled becaue of security policies or is being used by other apps
They say to do a factory reset but in some cases it doesn't work and the camera mysteriously just won't work so it appears to be a hardware error if that happens.........
It is unfortunate that LXC's dir mode is completely insecure and allows way too much information from the host to be seen. I wonder if there will eventually be a way to break into the host filesystem or other container's storage?
OpenVZ better security:
[root@ev ~]# cat /proc/mdstat
cat: /proc/mdstat: No such file or directory
/dev/simfs 843G 740G 61G........
Occasionally my whole screen locks up and I cannot even swith to the console and I find this in my syslog:
*-display
description: VGA compatible controller
product: Mullins [Radeon R3 Graphics]
vendor: Advanced Micro Devices, Inc. [AMD/ATI]
 ........
MySQL on Debian versions is configured differently than the native local MySQL plugin so you will be disappointed when your password on the mysql client fails by default.
Here is how you reset the MySQL root password the proper and "working way"
#first we gracefully stop mysql
sudo systemctl stop mysql;
#then we forcefully kill any mysqld process just in case
sudo killall -9 mysqld mysqld_safe;........
The reason for doing this is that the installer doesn't seem to work properly for LUKS and the server installer doesn't even support LUKS anymore. When you use the GUI install on Desktop for LUKS it won't boot and will just hang after you enter your password. So the only reliable way is to do it ourselves.
1.) Make a default minimal install of Ubuntu
2.) Have a secondary disk on the server or VM.
3.)........
Yes you have that right, the network service in RHEL8 / CentOS 8 / Rocky Linux / Alma Linux no longer exists. So there is no more systemctl restart network
You can restart NetworkManager but it doesn't have the same effect or ifup/ifdown on all interfaces.
Generally if NetworkManager is installed you will want to restart it or it won't apply the settings from ifcfg.
systemctl restart NetworkManager
To repl........
The cool thing here is that we only need 1 drive to make a RAID 10 or RAID 1 array, we just tell the Linux mdadm utility that the other drive is "missing" and we can then add our original drive to the array after booting into our new RAID array.
Step#1 Install tools we need
yum -y install mdadm rsync
Step #2 Create your partitions on the drive that will be our RAID array
Here I assume it is /dev........
This is the reason that I don't like the new ADATA USB drives such as the UV128/64GB or 128GB drives and other ones that look to be the same style (the green sliding USB connector).
They just don't work well from new and never work properly at any point.
[ 788.242463] usb 1-1.2: new high-speed USB device number 16 using ehci-pci
[ 788.339816] usb 1-1.2: New USB device found, idVendor=125f, idProduct=db8a
[ 7........
sudo vi /etc/lightdm/lightdm.conf.d/70-linuxmint.conf
Change this:
[SeatDefaults]
user-session=mate
allow-guest=false
To this:
[SeatDefaults]
user-session=mate
allow-guest=false
greeter-hide-users=true
greeter-show-manual-login=true
To see and apply your changes just restart light........
The problem is that by default ssh-keygen loves to generate an easy to crack 2048 bit key (RSA). Supposedly having a larger keysize helps such as 4096 or 8096 but it is thought to be useless still against Quantum computing.
How can I check my existing keysize and type?
ssh-keygen -lf /path/to/your/id_rsa.pub
The output will be something like below followed by the hash. The first number is the key size and the second part will b........
The reason we use the command below is because we need the md5sum value hash of the password. This means that we cannot use the md5sum
Change "yournewpass" to the pass you want to set
echo -n "yournewpass" | md5sum
Then you get the md5sum hash of whatever you entered eg. in this case "yournewpass"
5a9351ed00c7d484486c571e7a78c913 ........
This is a gotcha but be aware sometimes iptables may be active and loaded by default.
Also make sure you don't just disable firewalld but also stop it otherwise it will still block stuff:
systemctl stop firewalld
If the above is not the issue then it is possible iptables is running and blocking stuff too, so you'll need to stop iptables.
So in addition to opening firewalld or disabling it, you would need to disable iptables........
mysql reset root password.
Oops I can't remember my MySQL root password!
[root@centos7test etc]# mysql -u root -p
Enter password:
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
First we need to stop mariadb:
systemctl stop mariadb
Now we need to restart it with skip-grant-tables whic........
yum -y install mariadb-server
systemctl start mariadb
mysql_secure_installation
Now we need to secure our install and set the MariaDB root password:
The lines you need to act on are marked in bold shown with the answer you need.
mysql_secure_installation
NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB
SER........
yum install centos-release-scl
yum install rh-php72 rh-php72-php rh-php72-php-mysqlnd
Symlink PHP binary:
ln -s /opt/rh/rh-php72/root/usr/bin/php /usr/bin/php
Symlink Apache and PHP module config:
ln -s /opt/rh/httpd24/root/etc/httpd/conf.d/rh-php72-php.conf /etc/httpd/conf.d/
ln -s /opt/rh/httpd24/root/etc/httpd/conf.modules.d/15-rh-php........
This problem has been around forever, Linux seems to think it is fine to use the r8169 driver for an r8168 NIC but this often causes problems including the link not working at all.
In my case ethttool shows the link up and detected but it simply does not work especially on a laptop that has been resumed from suspension. Sometimes it takes several minutes for it to work or to unplug and replug the ethernet.
Here is the solution:
Install th........
Use fdisk on your USB drive to create a bootable NTFS partition (in my case /dev/sdb):
sudo fdisk /dev/sdb
Welcome to fdisk (util-linux 2.27.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): n
Partition type
p primary (0 primary, 0 extended, 4 free)........
There are many ways but a favorite way is to boot any Linux LiveCD and to use the syslinux package like so:
Just change the "sdx" to your sd for example /dev/sda or whatever the drive is that is supposed to boot Windows.
sudo dd if=/usr/lib/syslinux/mbr/mbr.bin of=/dev/sdx
0+1 records in
0+1 records out
440 bytes copied, 0.0197808 s, 22.2 kB/s........
A lot of times busy servers will have this issue and you cannot even force kill -9 the apachectl or httpd process:
[root@apachebox stats]# ps aux|grep httpd
root 1547 0.0 0.2 495452 32396 ? Ds Sep08 3:23 /usr/sbin/httpd
root 3543 0.0 0.0 6448 724 pts/1 S+ 13:11&nbs........
Most of us know the heredoc method but what if you need a basic query done repeatedly and manually while working from bash? It is a pain to manually type mysql and login each time.
With this command below you can semi-automate those queries:
echo "use somedb; select * from auctions" | mysql -u root --password="yourpassword"
Just modify the above to suit your needs and you can add more queries by adding a sem........
Oct 18 11:06:46 server systemd[529]: rc-local.service: Failed at step EXEC spawning /etc/rc.local: Exec format error
Oct 18 11:06:46 server systemd[1]: rc-local.service: Control process exited, code=exited status=203
Oct 18 11:06:46 server systemd[1]: Failed to start /etc/rc.local Compatibility.
Oct 18 11:06:46 server systemd[1]: rc-local.service: Unit entered failed state.
Oct 18 11:06:46 server systemd[1]: rc-local.service: Failed with result 'exit-code'.........
Create Database:
create database yourdbname;
Show All Databases:
show databases;
Change Database:
use mysql;
Drop / Delete a MySQL Database:
drop database nameofyourdatabase;........
Just edit your tftp file for xinetd like this:
*Change the IPto be the IPof the interface you want to listen on.
To test if your tftp is available on a certain IP range use nc -u yourip 69 to see if you can still connect (/var/log/messages or /var/log/syslog) should show the connection if it is open.
Oct 13 23:20:34 01 xinetd[26631]: Started working: 1 available servic........
sudo pip3 install python-docx
[sudo] password for :
Downloading/unpacking python-docx
Downloading python-docx-0.8.10.tar.gz (5.5MB): 5.5MB downloaded
Running setup.py (path:/tmp/pip_build_root/python-docx/setup.py) egg_info for package python-docx
no previously-included directories found matching 'docs/.build'
warning: no previously-included files matching '.DS_Store' foun........
service sshd status
● ssh.service - OpenBSD Secure Shell server
Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
Active: failed (Result: start-limit-hit) since Wed 2019-10-02 11:07:54 EDT; 36s ago
Process: 476 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=255)
Oct 02 11:07:54 box systemd[1]: Failed to start OpenBSD Secure Shell server.
Oct 02 11:07:54 box sys........
yum install iptables-services
systemctl enable iptables
service iptables save
iptables: Saving firewall rules to /etc/sysconfig/iptables:[ OK ]........
By default at least on Centos 7 nfs only allows 8 connections and starts 8 nfsd daemons.
To fix this edit this file:/etc/sysconfig/nfs
Edit the line "RPCNFSDCOUNT" (uncomment it so it looks like this:
RPCNFSDCOUNT=30
In the example above we are setting 30 nfsd daemons to run (or in other words 30 connections are possible this way).........
python3 testserver.com-car-scraping.py html.txt
Traceback (most recent call last):
File "testserver.com-car-scraping.py", line 5, in
import mysql.connector
ImportError: No module named 'mysql'
For some reason it won't install properly even though I have the mysql client on this machine installed too.
Solution:
You need the mys........
If you've just installed VBox and it is not starting or working, the most common problem is usually that you don't have your kernel source installed, which means there is no kernel driver for vbox so it can't work.
You may get an error that says "Kernel driver not installed" in your Virtualbox.
So the first thing you should do is install your kernel source by running this:
sudo apt-get install linux-headers-`uname -r`........
Install Errors on Version 12:
This error happened on QEMU emulator version 2.11.1 pve-qemu-kvm_2.11.1-5
on Proxmox/Debian but installing on QEMU.12 on Centos 6 did not produce the error.
*Update it is not related to the OS or QEMU version. This happened in Centos 6 too after a second install.
What really causes this even though you successfully install........
If you get error messages like this it is usually because /var/run/sshd does not exist.
root@userbox:/# service sshd status
● ssh.service - OpenBSD Secure Shell server
Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enab
Active: failed (Result: start-limit-hit) since Wed 2019-04-10 02:24:44 EDT; 1
Process: 511 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=255)........
I have seen this in a few rare cases after a reboot, where all folders and files will have the Read Only Attribute. If you uncheck it, it will just come back. It is more of a filesystem issue in Windows than a configuration issue and it looks like when Windows detects a badly corrupted filesystem that it will make things read-only, sort of like Linux would.
If you are Administrator or the owner of the folder and this is happening it is probably due to the reasoning mention........
The strange thing is that usually the first install or two will work on any new machine but then it suddenly won't. I had this experience on QEMU 2.13 on a different machine. There is something finicky or buggy about the CUCM installer even when choosing the same virtual hardware specs.
qemu-kvm command:
/usr/libexec/qemu-kvm -version
QEMU PC emulator version 0.12.1 (qemu-kvm-0.12.1.2-2.506.el6_10.1), Copyright (c) 2003-2008 Fabrice Bellard
........
This is the closest way to disabling it without using the "libata.force=noncq" kernel boot option is to set the queue to a depth of 1 which doesn't actually disable it.
Change the sdc below to match the device you want to disable NCQ for.
[root@officebox ~]# echo "1" > /sys/block/sdc/device/queue_depth
Errors that indicate you are having a performance issue are these in messages or dmesg relating to N........
chroot which stands for change root allows you to virtually operate in another operating system even though you haven't booted it. It is commonly used to deploy new distros, applications and to fix a broken Linux/Unix install or prep a new system image without having to physically boot the drive or disk.
So in this example let's say we have a drive that has a Linux OS installed on /dev/sdb1 and we have mounted this partition on /mnt/sdb1
The key point is to edit the &quo........
This is usually because of STP causing a delay in the negotiation.
Edit your ifcfg script eg:
/etc/sysconfig/network-scripts/ifcfg-eth0
Add a LINKDELAY of 30 seconds or whatever works for you:
LINKDELAY=30
After that you should have an IP during bootup.........
If you don't aleady have it, you'll need EPEL
Install LXC
yum -y install lxc lxc-templates
Loaded plugins: fastestmirror
Setting up Install Process
Loading mirror speeds from cached hostfile
* base: mirror.it.ubc.ca
* epel: mirrors.kernel.org
* extras: mirror.it.ubc.ca
* updates:........
This works on the 2000 and 3000 series generally.
*The easy way is to just hold the mode button for 10+ seconds.
The full/proper way is below:
1.) Either power on the unit and hold the "mode" button or hold the "mode" button until you see the below:
00:04:08: %SYS-7-NV_BLOCK_INIT: Initalized the geometry of nvram
00:04:08: %EXPRESS_SETUP-6-CONFIG_IS_RESET: The configur........
Idid a systemctl restart networking and it broke Proxmox VM connectivity!
#proxmox is the problem after restarting the network the tap devices go to disabled state
[2230884.919905] vmbr0: port 7(tap118i0) entered disabled state
[2230884.948864] vmbr0: port 8(tap122i0) entered disabled state
[2230884.972748] vmbr0: port 6(tap119i0) entered disabled state
[2230885.004745] vmbr0: port 5(tap117i0) entered disabled state
[2230885.03673........
The key thing here is to know the actual partition that is encrypted.
Often in Linux Mint's installer that ends up being partition 5 or /dev/sda5
sudo cryptsetup luksOpen /dev/sda5 anynamehere
You will then be prompted for your irrecoverable passphrase:
Enter passphrase for /dev/sda5:
If all goes well it won't say anything further. If it says ""No key available with this passphr........
This is not about systemd/systemctl and not about "onboot" so there's no rc.local trick here but it's the GUI/Gnome etc when a user logs in that a command is launched.
Put this in your home dir
The .config/autostart directory is where Linux Mint/Ubuntu checks for autostart application config files
mkdir -p ~/.config/autostart
Create a new entry/file that starts an application........
For most of these machines you just have to power the unit on while holding the "Del" key and you'll enter the BIOS.........
Do you hate how Centos 7 defaults to allocating most of your valuable space to /home even though it is a production server?
Here is a quick guide on how to take back that space live, while online (of course make sure you have backups just in case something goes wrong!):
First we will reduce our home dir by 100G:
lvreduce -L -100G /dev/mapper/centos-home
WARNING: Reducing active and open logical volume to ........
cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4]
md127 : active (auto-read-only) raid10 sdc1[0] sdb1[2]
1953382400 blocks super 1.2 512K chunks 2 far-copies [2/1] [U_]
resync=PENDING
bitmap: 15/15 pages [60KB], 65536KB chunk
Solution force repai........
I tried to stop a qemu-img copy or clone and it broke everything. It was fine to "stop" it from the GUI but a process still persisted so I killed the relevant qemu-img and the kernel went crazy. It also may not have helped that I tried to lvremove a different volume (an unused disk). But either way it breaks LVM (you cannot even run lvdisplay) so a reboot is necessary.
Jan 17 06:45:21 testserver kernel: [ 5680.439337] systemd-udevd D 0&nbs........
Below are the common errors you'll get with named AKA bind if your time is incorrect.
The simplest solution is to install and run ntpd to correct your system's time (install ntpd if it is not installed)
systemctl start ntpd
systemctl enable ntpd
Dec 20 13:36:16 hostingbox named[2169]: error (no valid DS) resolving 'develop.waxrain.com/A/IN': 14.215.150.17#53........
Set this in /etc/sysctl.conf
net.ipv6.conf.all.disable_ipv6 = 1
#apply the settings
sudo sysctl -p
........
On a test machine Iwas never able to access to a newly created 4th partiton. As we can see there are dev devices for everything but the 4th partition.
The normal "partprobe" or "kpartx" or kernel being told to rescan the block device didn't help (only a reboot did).
fdisk -l /dev/sda
Disk /dev/sda: 750.2 GB, 750156374016 bytes
255 heads, 63 sectors/track, 91201 cylinders
Units........
Before getting into the output here is my typical experience with SMART, there is what I call a "bad disk" with pending and uncorrectable sectors that cannot be reallocated.
It has caused a kernel panic and system crash repeatedly as we can see from the logs.
But SMART says it has "PASSED" its self assessment. SMART is still useful to me but it is more about looking at Current_Pending_Sector.
Any time I have had anything but 0 for that attribute it........
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/pdo_mysql.so' - /usr/lib64/php/modules/pdo_mysql.so: symbol mysql_options, version libmysqlclient_18 not defined in file libmysqlclient.so.18 with link time reference in Unknown on line 0
#not sure what is wrong with php-mysql but I removed it and installed mysqlnd
yum -y remove php-mysql
yum -y install php-mysqlnd........
# a single first slash means first occurrence
# format=${haystack/needle/replacement}
# if you use a double first slash it means ALL occurrences
# format=${haystack//needle/replacement}
email=${file/.txt-marked/}
In the example above we are searching in the variable $file for ".txt-marked" and replacing with nothing (the empty part after the last / means we are replacing with n........
Cisco's CUCM (Cisco Unified Communication Manager) is a system that combines voice, video, data and mobile products into a single unified management suite. At its core, the CUCMis like a "Super PBX" that controls the flow of all communications through an organization even single or multiple site deployments.
Cisco's CUCMmakes communication more effective and simple through centralized management and unification of communications resources.........
mytop is one of my favorite tools and it is fairly simple aside from a few caveats and issues that persist to this day.
To install it on Centos:
yum -y install centos
Configure ~/.mytop
vi ~/.mytop
user=root
host=localhost
db=test
#port=3306
socket=/var/lib/mysql/mysql.sock
header=1
color=1
Try runni........
systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system.
The key commands or arguments you will use with systemctl are the following:
Unit Commands:
list-units [PATTERN...] List loaded units
&nbs........
Did you just install the minimal version by accident or want to install the GUI? No need to reinstall just tell yum to do the work for you!
You could actually have both installed and choose one as your preference on demand (although many people prefer GNOME's simplicity).
Step 1.)
Install Gnome and/or KDE.
To install the GNOME Desktop on Centos 7:
yum -y groups install "GNOME Desktop"
To........
You can do other things but this particular script is just to set all AMD cards to 80% fan speed (remember this script needs to applied everytime you reboot). You could set it is a cron or just throw it into /etc/rc.local
basepath=/sys/class/drm
for hwmon in `ls -1 /sys/class/drm|grep card[0-99]$`; do
echo card=$hwmon;
hwmonname=`ls $basepath/$hwmon/device/hwmon|grep hwmon[0-99]`
hwmonpath=$basepath/$hwmon/device/hwmon/$hwmonname
echo "ec........
You'll have to violate the iso9660 standards but it is necessary if you want to preserve your filesystem and filenames and shouldn't be an issue as long as you are using a modern OS like Linux.
genisoimage -o Backup-Myfiles.iso -r -J -joliet-long /some/path/
You will get errors like below (even enabling joliet-long didn't help)
genisoimage: Error: /some/filename.pdf have the same Joliet name
Joliet tree sort failed. The -joliet-lo........
wget https://downloads.linux.hpe.com/repo/spp/rhel/6/x86_64/current/CP017004.scexe
--2018-08-16 05:11:16-- https://downloads.linux.hpe.com/repo/spp/rhel/6/x86_64/current/CP017004.scexe
Resolving downloads.linux.hpe.com (downloads.linux.hpe.com)... 15.249.152.85
Connecting to downloads.linux.hpe.com (downloads.linux.hpe.com)|15.249.152.85|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1525561 (1.5........
Error 0 occurred while receiving the document
root@vh1:/var/tmp# wget http://mirror.compevo.com/proxmox/proxmox-ve_5.2-1.iso
--2018-08-30 16:27:37-- http://mirror.compevo.com/proxmox/proxmox-ve_5.2-1.iso
Resolving mirror.compevo.com (mirror.compevo.com)... 103.25.61.44
Connecting to mirror.compevo.com (mirror.compevo.com)|103.25.61.44|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 641517568 (612M) [application/o........
Your database uses Antelope as the file format. Full UTF-8 support in MySQL and MariaDB requires the Barracuda file format. Please switch to the Barracuda file format. See the documentation MySQL full unicode support for details.
In /etc/my.cnf under [mysqld]
180827 21:43:14 InnoDB: 5.5.59 started; log sequence number 1589339
180827 21:43:14 [ERROR] /usr/libexec/mysqld: unknown variable 'db_file_format=Ba........
How to check if nested KVM is enabled by doing a cat on nested inside sys
Nested KVM is mainly important for testing for example if you wanted to install VMWare or Proxmox Nodes in a virtual environment for testing. Without nesting, the performance will be extremely slow, since the VMs within the nodes will not be using Virtualization extensions.
I've used wildcard on kvm_ because it could be kvm_intel or kvm_amd depending on whether y........
This is not so much of a vi error as it is a physical filesystem error in the sense that the file you are trying to write to is a symlink and the destination doesn't exist or for some other reason is inacessible.
So vi is tellng you "you're writing to a symlinked file and the file the symlink points to cannot be written to". This is especially highlighted byt he fact that if you are using wq! to write and you still get the error.........
zenity is a nice utility as part of the gnome window manager that allows you to script from bash and retrieve the input from the user. It could also be helpful in just notifying a user when they login with a popup window.
I'll give an overview of what's available with zenity:
Application Options:
--calendar Display calendar dialog
--entry Display tex........
Error reading from database
More information about this error
It is usually not possible to recover from errors triggered during installation, you may need to create a new database or use a different database prefix if you want to retry the installation.
Solution:
This happened when I was running MySQL 5.1. Assuming your database details are right and the DB is up then make sure you are usin........
Almost always the reason will be that the php.so file is missing but also that php.conf is misconfigured.
In the problem machine it is actually PHP7 installed so if you reference PHP5 of course things wil be broken!
Take for example here:
cat /etc/httpd/conf.d/php.conf
#
# PHP is an HTML-embedded scripting language which attempts to make it
# easy for developers to write dynamica........
Aug 10 01:11:54 mailserver postfix/smtp[6180]: 020AE17C2BD1: to=, relay=none, delay=0.29, delays=0.28/0/0/0, dsn=5.4.4, status=bounced (Host or domain name not found. Name service error for name=gmail.con type=A: Host not found)
A user complained that their e-mails weren't being delivered but they actually made a small typo and used gmail.con so it wasn't working as expected of course........
sudo apt-get install libcurl4-openssl-dev git build-essential autotools-dev autoconf libcurl3
sudo apt-get install libcurl4-gnutls-dev
git clone https://github.com/wolf9466/cpuminer-multi
sudo apt-get install cmake libpthread-* libmicrohttpd-dev libssl-dev libhwloc-dev
git clone https://github.com/fireice-uk/xmr-stak-cpu.git
make install
cd bin
chmod +x xmr-stak-cpu
./xmr-stak -O xmr........
This is often the result of PayPal's "item name" or another name having invalid characters or not supporting Unicode.
173.0.81.1 - - [17/Jul/2018:13:39:45 -0400] "POST //modules/gateways/callback/paypal.php HTTP/1.1" 406 - "-" "PayPal IPN ( https://www.paypal.com/ipn )"
A good clue is if you check the debug output of the IPNand find a mandatory column empty.
........
Server Side Config
1.) First install nfs-utils
yum -y install nfs-utils
2.) Configure nfs share
Create a directory for your NFS share
mkdir /datastore
Create your NFS share in /etc/exports
echo "/datastore 10.220.101.0/24(rw,sync,no_root_squash)" >> /etc/exports
systemctl restart nfs........
We all know Linux is known for good memory management but is it really? It seems all on its own with hardly anything running that you can come back in days or weeks and find that almost all of your RAMis used!
And many will say "no don't worry it's buffers for optimization" but it doesn't seem to help because what is in buffers is not available to use for new programs running or ones that allocate more RAM as far as Ican tell.
The reason Iknow........
You can search for this bug and it seems like it may be related to ecryptfs and is many years old.
The symptoms are that you return to the computer and the screensaver was active or the screen was asleep/black and it doesn't seem to come back. But you check by SSH the computer is running fine and are frustrated you'll lose your running programs and have to reboot.
There is a simple solution:
Ctrl + Alt + F1
Ctrl +Alt + F8
Ba........
nfs mount failed:
mount 10.10.2.20:/tmp/nfsmount /mnt/nfs/
mount: wrong fs type, bad option, bad superblock on 10.10.2.20:/tmp/nfsmount,
missing codepage or helper program, or other error
(for several filesystems (e.g. nfs, cifs) you might
need a /sbin/mount. helper program)
 ........
Intel VT-X is enabled in Virtualbox but it doesn't seem to pass through the needed vmx extension despite the following variables on the host confirming it is enabled:
cat /sys/module/kvm_intel/parameters/nested
Y
cat /sys/module/kvm_intel/parameters/ept
Y
OVF Tool: Disk progress: 99%
OVF Tool: Transfer Completed
OVF Tool: Powering on VM: Embedded-vCenter-Server-Appliance-
OVF Tool: Task p........
#mount the VCSA DVD
mount /dev/sr0 /mnt/cd
#alternatively you could mount the iso directly
mount -o loop vcsa.iso /your/mount/path
#for this purpose we are using the CLI installer on Linux
cd /mnt/cd/vcsa-cli-installer/lin64
#no it's not going to be that easy you can't just run vcsa-deploy like that you need to use a template or configured .json file
./vcsa-deploy
Usage: vcsa-deploy [-h] [--version] [--supported-deploymen........
This is most likely to happen on a normal GUI system like Ubuntu or Linux Mint. If you or the user is meant to have sudo / root privileges it is as simple as editing the following files:
Now assume your username is "iamtheuser"
vi /etc/group
adm:x:4:syslog,iamtheuser
sudo:x:27:anotheruser,iamtheuser
Find the above lines and add a comma and "ia........
Database Error
One or more of the WHMCS database tables appear to be either missing or corrupted. Please check and repair.
This error can be misleading especially if you know you are using a known good backup or restoration of the WHMCS database. The error can also be that the user lacks permissions to read and write to the database.
To check to this in MySQL shell:
GRANT read,write to dbusername@localhost on dbna........
This is not the normal "black screen"issue and I was shocked to eventually find out why. The normal advice of reconfiguring Xorg didn't work. Even booting into "Recovery Mode" did not help.
Here is the short end of the stick that fixed it:
sudo apt-get install mdm mate-desktop-environment
Yes you got it right, mdm and the mate-desktop-environment / gnome were somehow uninstalled. This must be whe........
This usually happens when you are using something like an INT and try to insert a larger valuethan the maximum which is larger than "2147483647"
On a practical term I have seen this and been guilty of this error when using scripts like PHPand generating large random numbers:
$hash = mt_rand(5,9999999999999);
Obviously that many 9's are more digits than the maximum of an INT resulting in that error. Change your code accord........
ValueError: new value non-existent xfs filesystem is not valid as a default fs type
Pane is dead
From what Iread this is misleading and has to do with the fact that the initrd and kernel are mismatched.
This is a hard situation because for some older hardware Iam using the Centos Plus kernel which has modules that Irequire for an older server/NIC. This seems to have cropped up in the past few months and there is no simple fix........
This is one thing that has me wondering about SMF. It is apparently a known issue but in the latest version and new install nothing looked right because it was using http://127.0.0.1 to find everything! How on earth would it ever do this or think it is normal?
Excerpt of crazy html code it produces that causes the issue:
........
It is simple the user just needs to be given the "LOCK TABLES" privilege.
As root run this command:
GRANT LOCK TABLES ON yourdatabase.* TO yourmysqluser@localhost;........
GRANT SELECT, LOCK TABLES ON *.* TO yourmysqluser@localhost;
All you need to do a full MySQL dump on all databases is the SELECT and LOCK TABLES privileges. This way you don't have to use the mysql root user. Data could be compromised this way but at least no harm from manipulation, changes or deletion are possible by locking down the privileges to the minimum for a full MySQL dump and backup.........
It's fairly simple to start or stop a check but I do wish mdadm's command had this built in. Sometimes it will do a check at the worst time causing the server to crawl to a halt.
Stop check on md126:
echo idle > /sys/block/md126/md/sync_action
Start check on md126:
echo check > /sys/block/md126/md/sync_action
........
Starting container...
vzquota : (error) Quota on syscall for id 4532: No such file or directory
vzquota on failed [3]
Solution
vzquota drop 4532
Then start the container and it should work. It actually happened after migrating the VPS manually to ano........
Just type the command:
localboot
By default it will boot the first local drive "0". Ibelieve you can specify a different number to boot a different device.
eg.
localboot 3
(will boot the 4th BIOS device)'........
The easiest way is to use SSHand DD or a combination of netcat. SSHwill be a little slower due to encryption but is the most secure way (on two older systems the average clone speed is about 40-50MB/s). This is also OS independent as it doesn't matter what the source OS is because you are literallly cloning the drive so you retain the partition table and settings.
Clone HDD using SSH and DD........
I don't recall having this issue in the distant past but nowadays at least Debian seems to be very picky about this.
I used dd to copy one hard drive to another and tried booting it. Everything seemed fine with grub working but each time it would drop to the busybox shell. There is no particular error so this is misleading.
Normally the first things you would check are to make sure your fstab is correct (that the UUID is correct)and that you've updated grub.&........
This guide will work for most modern Linux versions like Centos RHEL 7, Debian, Mint, Ubuntu etc...
In Centos 7 the days of editing the "kernel"line and adding "single"are gone. On top of that sometimes after a new install passwords do not work, maybe you forgot your password or for some other reason you need to break in or fix your system? It could also be because you can't mount your root / or some other /etc/fstab error and many other err........
ALTER TABLE existingtable ADD newfieldname VARCHAR(255);........
This happened on Centos for no apparent reason with no obvious issue in the logs. Data could be read fine but not written (possibly due to some corruption or out of memory issue in the OpenVZ container is the best guess).
All mysql update and insert queries failed freezing without any error log on any database and table.
Tried to restart:
service mysqld restart
Timeout error occurred trying to stop MySQL........
MySQL will silently truncate a larger INT than capable.
Check MySQL's own documentation here:
As we can see the maximum size of INT (which is the most commonly used) is 2147483647
A lot of coders make this mistake by using very large values such as 9999999999 but it would actually truncate to 2147483647 which is the maximum size of an INT. This is dangerous beca........
ALTER TABLE thetable ADD newfield VARCHAR(255)
It's very simple just specify "the table" and then the newfield type........
The commands below will help you reset any mysql user password.
use mysql;
update user set password=PASSWORD('thenewpass') where User='theusername';
flush privileges;
The first line says to use the "mysql" database which contains all the user info.
the second update line sets the new password "thenewpass" for the u........
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/geoip.so' - /usr/lib64/php/modules/geoip.so: undefined symbol: GeoIP_country_code_by_name_v6 in Unknown on line 0
Remove the GEOIP from PHP:
php71w-pecl-geoip-1.1.1-1.w6.x86_64
PHP Fatal error: PHP Startup: apc_shm_create: shmget(0, 67108864, 914) failed: Invalid argument. It is possible that the........
The Linux Kernel interpretated a very high volume of real traffic as a DDOS attack so it basically ends up blocking your web server.
possible SYN flooding on ctid 42131, port 80. Sending cookies.
Simple fix edit sysctl values for max_syn_backlog
sysctl -w net.ipv4.tcp_max_syn_backlog=5000
To make them permanent edit /etc/sysctl.conf
echo "net.ipv4.tcp_........
yum -y install samba
vi /etc/samba/smb.conf
https://www.kernel.org/pub/linux/utils/boot/syslinux/syslinux-6.03.zip
mkdir syslinux;cd syslinux;unzip syslinux-6.03.zip
mkdir -p /tftpboot/libs/
cp bios/com32/modules/linux.c32 /tftpboot/libs/
cp bios/com32/libutil/libutil.c32 /tftpboot/libs/
cp bios/com32/lib/libcom32.c32 /tftpboot/libs/
#add lib path
echo "PATH libs" >> /tftpboot/pxeli........
Normally lspci will show you just like this and would suggest they are exactly the same card:
1a:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/580] (rev e7)
1c:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/580] (rev e7)
lspci -vnn is the answer
As we can see one is a Gigabyte and the other is an MSI card. Wha........
pcimodules no longer works it produces nothing probably because the format of /sys/bus/pci is different.
lspci -k doesn't work on older lspci versions.
pciutils can be compiled but it won't work if you have an old system and compile on a newer glibc.
iteriate through /sys/bus/pci/devices/*/modalias
cat /sys/bus/pci/devices/*/modalias
pci:v00008086d00001237sv00000000sd00000000bc06sc00i00
pci:v00008086d00007000sv0000000........
edit theme css:
Click "Appearance -> Editor -> Stylesheet"
http://yourblog.com/wp-admin/theme-editor.php?file=style.css&theme=twentysixteen
textarea {
color: #1a1a1a;
/*font-family: Merriweather, Georgia, serif;*/
font-family: "Lucida Sans Unicode", "Lucida Grande", sans-serif........
Check for crap in /var/lib/mysql like this
ls -al /var/lib/mysql/
total 20888
drwxr-xr-x 24 mysql mysql 4096 Oct 3 18:30 .
drwxr-xr-x 20 root root 4096 Oct 3 04:23 ..
-rw-rw-rw- 1 mysql mysql 11776 Oct 3 17:10 c:exp.exe
-rw-rw-rw- 1 mysql mysql 48128 Oct 3 17:10 c:exp1.exe........
guestmount -a kvmuserscra.img -m /dev/sda1 mount
libguestfs: error: mount_options: /dev/sda1 on / (options: ''): mount: unknown filesystem type 'ntfs'
guestmount: '/dev/sda1' could not be mounted.
guestmount: Did you mean to mount one of these filesystems?
guestmount: /dev/sda1 (ntfs)
guestmount: /dev/sda2 (ntfs)
yum -y install ntfs-3g
still........
Upgrading from PHP 5.3 to 5.4+ there are many challenges basic things like mysql_connect() do not work anymore.........
A great way if you have a bunch of drives and mdadm connected and are looking for backups/archives and don't know what is where!
for md in `cat /proc/mdstat|grep md[0-99]|awk '{print $1}'`; do mkdir /mnt/$md; mount /dev/$md /mnt/$md; done........
You are using Centos 5 which is deprecated so nothing in yum will work until you follow this post to use the vault:
http://realtechtalk.com/Centos_59_Working_Vault_Repo_file-1921-articles
yum update
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* epel: fedora-archive.ip-connect.vn.ua
Traceback........
mysqldump or mysql query of a larger file/table
ERROR 2006 (HY000) at line 567: MySQL server has gone away
Add this to /etc/my.cnf
max_allowed_packet=64M
service mysqld restart........
myisamchk can fix it
But be careful and use the right options to avoid losing data. In fact if you haven't you should make a backup or at least manually copy /var/lib/mysql.
Replace "YourDB" with the name of your database
Replace "yourcrashedtable" with the name of your crashed table.
The -o option is the safest and should avoid dataloss whereas -r is more aggressive and is a last option (I have lost data using -r and........
Iam not sure why this is happening neither the hostnode or VM changed. All I did was reboot the hostnode and startup the Centos VM again, also note it happened with the original kernel on the VM and also the latest 6.9 kernel as of this writing as shown below.
Host Node: Centos 6.9
Kernel:2.6.32-696.6.3.el6.x86_64
Kernel: 2.6.32-042stab123.9
Same result in any kernel above........
sudo tar --ignore-failed-read -czvf mycomputer-backup.tar.gz --exclude=/home/otheruser/* --exclude=/proc/* --exclude=/sys/* /
Note the --exclude clauses and modify/add according to your needs........
This is an important feature a failed read can genuinely occur if a temporary file has been removed or if you try backing up a sysetm file in /proc /sys (which you shouldn't really anyway).
The way to fix this is the following switch:
--ignore-failed-read
Example:
sudo tar --ignore-failed-read -czvf mycomputer-backup.tar.gz --exclude=/home/otheruser/* --exclude=/proc/* --e........
When using the .sh script the rendering doesn't work after an upgrade of related packages to kdenlive.
kdenlive (kdenlive:amd64 (4:17.04.1+git201705191233~ubuntu16.04.1)) with affine or composite transitions was fine but is now broken during the time of transition it is just a white screen.
The previous version was fine:
kdenlive:amd64 (4:17.04.1+git201705191233~ubuntu16.04.1
But now I can't find it or install it:........
cagecoin linux compile:
sudo apt-get install qt4-qmake libqt4-dev build-essential libboost-dev libboost-system-dev
libboost-filesystem-dev libboost-program-options-dev libboost-thread-dev
libssl-dev libdb++-dev libminiupnpc-dev
Solution:
sed -i s/"BOOST_LIB_SUFFIX=-mt-s"/"#BOOST_LIB_SU........
Essentially a program I was running for mining did not terminate properly with Ctrl+C it is listed as defunct and cannot be killed, kernel is tainted and normal tricks to disable the port are impossible the dev and sys entries for the device cannot be browsed or interacted with in any form without a lockup of the request. The only solution is to reboot due to the kernel taint as far as I can find so far.
[1130246.811056] INFO: task minerd:21861 blocked for more th........
#if you have nvidia make sure you install the nvidia-cuda-toolkit so hardware acceleration can be used
wget http://ffmpeg.org/releases/ffmpeg-3.3.2.tar.bz2
tar -jxvf ffmpeg-3.3.2.tar.bz2
cd ffmpeg-3.3.2/
./configure --disable-yasm
install prefix /usr/local
source path ........
Some guides still use the old Centos 6 style (do not use /etc/sysconfig/network).
In Centos 7 the file is /etc/hostname
echo "HOSTNAME=yourhostname.com" > /etc/hostname........
Done on Centos 7.3 very important as clearly based on older guides it was a lot easier and more simpler! Hint do not use grub2-install!
If you have trouble booting after this check this CentOS mdadm RAID booting/fixing guide.
One huge caveat if you are an oldschool user or sysadmin who has avoided UEFIbooting
The nor........
user@box:~$ sudo tune2fs -l /dev/md99
[sudo] password for user:
tune2fs 1.42.9 (4-Feb-2014)
Filesystem volume name:
Last mounted on: /mnt/md50
Filesystem UUID: 976a8655-2619-4587-878c-dab07f7b7652
Filesystem magic number: 0xEF53
Filesystem revision #: 1 (dynamic)
Fi........
Still looking for the solution
Working Solution 2017/07
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys D46F45428842CE5E
Solution
gpg --keyserver hkp://subkeys.pgp.net --recv-keys D46F45428842CE5E
gpg: requesting key 8842CE5E from hkp server subkeys.pgp.net
gpg: keyserver timed out
gpg: keyserver........
This is a 8TB Seagate external USB 3.0 device apparently newer kernels use a module called "UAS" instead of "USB Storage" which causes issues as a lot of devices are not properly supported in UAS mode by the kernel driver. The solution some say is to disable UAS specifically for your USB device but I'd rather just disable UAS altogether.
Solution blacklist UAS: *do not do this it does not work and just causes your USB 3.0........
When running cudaminer once it tries to initialize the card the entire screen freezes. The computer itself is still running but the Xorg is done for, you cannot even switch to another console window and must reboot (even an mdm or Xorg restart does not help).
At first cudaminer will give you these errors:
stratrum_recv_line failed
...retry after 15 seconds
GPU #0: Geforce 210 with compute ca........
Here is a simple MP3 player and now there's a reason to understand why the supplied cable has some kind of capacitor and is very short. These devices can be VERY finicky and any voltage fluctuation or difference is enough to cause issues.
Take for example the error messages from Linux Mint:
[804829.895414] usb 1-1: USB disconnect, device number 11
[806961.109030] usb 1-1: new high-speed USB device number 12 using xhci_hcd........
Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Missing folder chosen by user:
Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Removed missing file: MAH02949.MP4
Jun 1 15:45:57 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: ui_util:WARNING Icon theme media-playback-start not found. Will use backup........
I was sure this was a Centos bug with OpenSSL, Apache, MySQL or even PHP. I tried everything but nothing helped. One clue is that if you check the Apache logs you will see nothing in the access logs until minutes later (this means Firefox has not even passed your request to the remote Apache/htttpd server).
When even accepting the invalid certificate message that would show up minutes later when trying to "View the Certificate" Firefox would freeze. This bu........
I'm getting this error randomly but suspect it is an update or application conflict. It also takes ages for this "collection" to happen.
"system_thread_exception_not_handled (srv.sys)"........
To grant the IP 192.168.2.4 to user mysqlguy
GRANT ALL ON *.* TO 'mysqlguy'@'192.168.2.4';
To allow any IPfor mysqlguy just use the wildcard % character
GRANT ALL ON *.* TO 'mysqlguy'@'%';
Also note it is normal and fine to have multiple entries in the mysql table.........
Error while connecting to MYSQL: (XID 4ea7s9) Access denied for user 'root'@'localhost' (using password: YES) at /usr/local/cpanel/Cpanel/Mysql.pm line 181
Solution
This error occurs because the /root/.my.cnf has the wrong/outdated password for MySQL root user. Simply edit /root/.my.cnf with the correct user. This normally happens if you update outside of cPanel.........
Centos 7 is no cakewalk, there are many fundamental features and basic utilities that are missing or even completely renamed or different!
Another shocking thing is to check your NIC it is set by default to not turn on when booting!
And by the way there is no more standard eth0 the NIC convention is now "enp0s3"
vi /etc/sysconfig/network-scripts/ifcfg-enp0s3........
1.) Replicate the number of partitions in your new drives.
gdisk /dev/sda
gdisk /dev/sdb
I created 3 partitions of the same same size.
partition #1: +1G (/boot)
partition #2: +60G (swap)
partition #3: rest of it (/)
#note if you are using GPT/gdisk you need to create separate a partition at least 1MB in size (in my case I would a 4th partition and mark it type ef02).........
mdadm won't boot in Ubuntu/Mint/Debian anymore.
You just get the following in a loop:
mdadm: CREATE group disk not found
Incrementally started RAID arrays.
Incrementally starting RAID arrays...
mdadm: CREATE group disk not found
Incrementally started RAID arrays.
Incrementally starting RAID arrays...
mdadm: CREATE group disk not found
Incrementally started RAID arrays.
Incrementally starting RAID arrays...
mdadm: CREATE group dis........
Solution:
yum -y install --skip-broken package-you-want-to-install
Packages skipped because of dependency problems:
php56w-mysql-5.6.30-1.w6.x86_64 from webtatic
Error: Multilib version problems found. This often means that the root
cause is something else and multilib version checking is just
pointing out that there is........
Ifigured out what caused this but don't have the solution just yet. Iwould deploy a certain script from a .tar.gz to some servers and found that /root was always owned by user and group "1000.1000". This corresonded to the user who made the .tar.gz.
For some reason when extract normally with "tar -zxvf file.tar.gz" it impacts the parent directories ownership. There must be some recursion going on or possibly the .tar.gz but I haven't f........
In short the solution is just to use vgremove for the actual /dev/mapper device:
vgremove /dev/mapper/backups-backuplv
box mnt # mdadm --manage /dev/md8 --stop
mdadm: Cannot get exclusive access to /dev/md8:Perhaps a running process, mounted filesystem or active volume group?
box mnt # lv
lvchange lvconvert lvcreate l........
This was a surprising bug but I unplugged all drives for an array md127. At first it was just 1 drive and mdadm seemed to notice this. I unplugged the second drive taking the array offline but mdadm did not realize it was offline and still showed a non-existent disk as being part of it. This created problems trying to unmount it or even to stop this array with mdadm freezing.
As for how to fix it I can only think of making sure you are not in a mounted path of........
The solution is simple but strange, if you copy your /var/lib/mysql directory to another server and think it will work, be sure to check if you have /var/log/mysql and binary log files. If you do, the server will not work and will give you errors like below and crash without the proper log files.
UPDATE user SET password=password("newpass") WHERE user='root';
flush privileges;
ERROR 2013 (HY000): Lost connection to MySQL server durin........
The "-S" switch is important as it works with sockets if you use "-f" it will not detect the socket file is there.
if [ ! -S "/var/lib/mysql/mysql.sock" ]; then
echo "Socket does not exist, restarting"
service mysqld restart
fi........
PHP Fatal error: PHP Startup: apc_shm_create: shmget(0, 67108864, 914) failed: Invalid argument. It is possible that the chosen SHM segment size is higher than the operation system allows. Linux has usually a default limit of 32MB per segment. in Unknown on line 0
PHP Fatal error: PHP Startup: apc_shm_attach: shmat failed: in Unknown on line 0
This error is not at all fun because it actually prevents Apache/httpd from starting or working at all. It will........
170110 5:35:23 [Note] /usr/libexec/mysqld: Normal shutdown
170110 5:35:23 [Note] Event Scheduler: Purging the queue. 0 events
170110 5:35:23 InnoDB: Starting shutdown...
170110 5:35:24 InnoDB: Shutdown completed; log sequence number 0 12765401
170110 5:35:24 [Note] /usr/libexec/mysqld: Shutdown complete
170110 05:35:24 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended........
Change Host="192.168.5.99" with the remote IP allowed(this is of course more secure but also cumbersome if your IP changes). You could also have a single layer of protection that specifies the IP via firewall or both (of course both are far mor secure).
UPDATE user SET Host="192.168.5.99" where Host="localhost"
or for any/wildcard
UPDATE user SET Host="%" where Host="localhost&qu........
I created a new partition table on a newly plugged in device and it caused fdisk to hang (even force kill does not work). It also may be a bad drive or some other issue because fdisk -l hangs after the first 2 HDDs (totaly of 8 HDDs on this system):
[1232879.903596] INFO: task fdisk:27176 blocked for more than 120 seconds.
[1232879.903607] Tainted: P&nbs........
sudo fdisk /dev/sdh
WARNING: GPT (GUID Partition Table) detected on '/dev/sdh'! The util fdisk doesn't support GPT. Use GNU Parted.
WARNING: The size of this disk is 8.0 TB (8001563221504 bytes).
DOS partition table format can not be used on drives for volumes
larger than (2199023255040 bytes) for 512-byte sectors. Use parted(1) and GUID
partition table format (GPT).
The device presents a l........
You are checking your MySQL logs in /var/log/mysqld.log and come across an error like this:
161222 18:03:40 [ERROR] /usr/libexec/mysqld: Table './eximstats/sends' is marked as crashed and last (automatic?) repair failed
The Solution:
cd /var/lib/mysql/eximstats
myisamchk -r sends.MYI
- recovering (with sort) MyISAM-table 'sends.MYI'
Data records: 71129........
iptables -t nat -A OUTPUT -m addrtype --src-type LOCAL --dst-type LOCAL -p tcp --dport 3306 -j DNAT --to-destination ip.ip.ip.ip
iptables -t nat -A POSTROUTING -m addrtype --src-type LOCAL --dst-type UNICAST -j MASQUERADE
sysctl -w net.ipv4.conf.all.route_localnet=1
Make sure you substitute "ip.ip.ip.ip" for your real public IP and also the "--dport 3306" for the port you want to forward.
Finally run the sysctl command and........
Tired of checking iotop and seeing that your drbd partition is using 99.99% of io all the time and finding your drbd device performs slow in general?
This is especially an issue in versions of DRBD in the 8.3 tree in particular one documented case is on "8.3.13" but it likely applies to other devices.
The symptoms are that resyncing is fine and normal but any reasonable amount of activity is very slow and lagged and creates a high server load and con........
To disable NCQ in the Linux kernel (change sda to match your device).
echo 1 > /sys/block/sda/device/queue_depth
To enable NCQ (change sda to match your device).
echo 31 > /sys/block/sda/device/queue_depth........
We've all done this at some point, you work on the wrong shell window and this was my first time making this mistake but I deleted a partition table in fdisk, recreated it and saved it with "wq" and even ran partprobe! If you haven't rebooted yet then you can still recover your partition table, otherwise you're in big trouble.
Fortunately since it was a live system and in use the kernel still had to use the old table like below:........
rm /vz/lock/1200.lck
rm: remove regular file `/vz/lock/1200.lck'? y
vzctl start 1200
Container already locked
vzctl start 1200
Starting container ...
vzquota : (error) can't lock quota file, some quota operations are performing for id 1200
vzquota on failed [7]
vzquota off 1200
vzctl start 1200
vzquota on 1200
root@rttbox ~]# vzquota off 1200
vzquota : (........
This happened while an mdadm array was syncing, all access from writing a new blank file to opening a small .txt file was very slow:
[222117.312078] kjournald starting. Commit interval 5 seconds
[222117.685060] EXT3-fs (md0): using internal journal
[222117.685096] EXT3-fs (md0): mounted filesystem with ordered data mode
[222122.376847] kjournald starting. Commit interval 5 seconds
[222122.602825] EXT3-fs (md2): using internal jour........
kernel: [10186978.064405] TCP: time wait bucket table overflow (CT3)
Varying opinions are out there but in general it seems like the most common culprit is a lack of privvmpages, with a modern OpenVZ system the best way is to set privvmpages as equal to what your RAM is and this has resolved the messages on another system.
If it's truly a TCP issue you can adjust the following parameters:........
This is a common mistake but many people do not realize this function comes from mysql itself, so therefore you need an active mysql connection open.
Usually the string will be empty and null when you call it from outside of the database connection portion of your code.
eg. an example of the wrong way and creating a null/empty string
$var = mysql_real_escape_string($myself)
mysql_connect();
// returns n........
pip install obfsproxy
/usr/lib/python2.6/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.
InsecurePlatformWarning
You are using pip version 7.1.0, however version 8.1.1 i........
At first my BIOS said the card may not work right because there is no more option ROM space.
I disabled the Option ROM for both LSI 1068 and 2008 chipsets, Network Boot ROM and most other PCI slots, Serial Port, etc... and the message went away but the card still does not work properly.
But it still cannot initialize the card properly(does not work):
[ 33.943272] NVRM: This PCI I/O region assigned to your NVIDIA device is invalid:........
I modified the default to the following for faster local dialing for North American area codes:
(*xx|[3469]11|0|00 [2-9]xxxxxxS0|[2-9]xxxxxxxxxS0|1xxx[2-9]xxxxxxS0|xxxxxxxxxxxx.)
This is what I added to the above: "[2-9]xxxxxxxxxS0" so any 9 digit number is dialed instantly xxx-xxx-xxxx (the S0 at the end makes it dial right away). This makes dialing much quicker and is recommended.
*No........
I have two lines on my PAP2T and the only thing that solved this problem rather instantly was to change the line with the problem to using port 5060 instead of 5061 (so both lines are using port 5600). Note that I am not forwarding either port in my router either.
Some of the symptoms of this problem for me were the following:
No dialtone or it would take several tries.
You answer a call but the phone keeps ringing (takes a few times t........
service iptables start
iptables: Applying firewall rules: iptables-restore: line 40 failed
[FAILED]........
The first thing to diagnose is what is actually in the database (use PHPMyAdmin or CLI).
You will of course either find that the backslash is either in the database or not.
If the backslash is in the database you probably have magic quotes gpc/runtime on and/or are calling the "addslashes()" function which does this.
If you are escaping your data with mysql_real_escape_string() then think again, you probably have magic quotes gpc enabled either in php.ini or........
1.) Flash directly to this file:
http://tomato.groov.pl/download/K26RT-N/build5x-132-EN/Linksys%20E-series/tomato-E2500-NVRAM60K-1.28.RT-N5x-MIPSR2-132-Max.zip
*I was never able to get the larger "Mega" file to work, at least not initially so I recommend the file above.
To enable 5ghz I had to do the "Clear NVRAM" Option before it was shown.
2.) Or if you don't need 5ghz (most devices do not support it and cannot........
The problem is that the default of most of these units is set for non-North American phones so the ring sounds like it cuts off and is not sequential.
How To Fix the Issue
Click on "Regional" and make sure you are in Advanced mode.
........
The Scenario
You have dual NICs and you disable NIC1 which uses 192.168.1.1 as its gateway. With NIC2 you enable it/connect it to another network which also has the gateway 192.168.1.1
Everything will work fine at this point.
When switching back to NIC1 even with NIC2 disabled and even unplugged, the OS basically can't pick up the new/updated ARP entry of the old device for 192.168.1.1 and perhaps thinks it is a security risk or spoof of some sorts and blocks i........
Iwill start by saying I think I know what caused this boot-time error on Linux Mint but should also apply to Debian and Ubuntu.
I changed my BIOS time to several hours in the past to match the current time, but this caused Linux to think there were incorrect filesystem times.
The problem is that it seems when you hit this I am not sure what is happening, it doesn't seem to be doing fsck and hangs without prompting the user.
What I have found is that........
Add the following to fstab where 192.168.1.125/Media is the samba share and where /home/homeuser/Downloads is where you want to mount.
Change user and pass to what is needed (if no pass is required it still works fine with the below).
//192.168.1.125/Media /home/homeuser/Downloads cifs user=guest,pass=bla 0 0
mount: wrong fs type, bad option, bad superblock on //192.168.1.125/Media,
&nbs........
This is actually very simple and this example assumes your network device is "eth0"
In Centos your network config would be the following: /etc/sysconfig/network-scripts/ifcfg-eth0
Take the same path and just add a "-range0"
So to add a range create the following file: /etc/sysconfig/network-scripts/ifcfg-eth0-range0
IPADDR_START=192.168.1.50
IPADD........
grub> root (hd0,0)
root (hd0,0)
Filesystem type is ext2fs, partition type 0xfd
grub> setup (hd0)
setup (hd0)
But if you do:
root (hd1,0)
setup (hd1)
it does work, I think hd0/sda had a GPT partition that was not removed properly (what I did was just dd bs=512 count=1 the partition table from another drive since the partition table should be identical).
Checking if "/boot/grub/........
How to Increase The Disk and Partition Size in Windows 2022,2019,11,10,8,7 etc.. Server
1, Enter the command prompt
Start -> cmd
2. Start diskpart
diskpart
3. Find the drive that has the wrong size
list volume
4. Select the volume (in this example we use volume 2)
select volume 2
5. Extend the volume........
INSERT INTO articles_backup
SELECT * FROM articles WHERE articleID="118"
It is so simple we always recommend people do this when updating their database so you always have a backup.
The above inserts the copy into the table "articles_backup" which has an identical structure.
It selects the entry from "articles" where the articleID is "118" but of course you can adapter yours to whatever the situation is.........
Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason. Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to? In some cases on a remote system you can't easily reinstall without physical or KVM access.
So in this case you add a second physical or disk or already ha........
In my case I could login with the initial install but I rsync'd everything over while preserving ownership and permissions to another RAID partition and booted from that.was fine before. The problem is that you are kicked out the second you login and the problem was SELINUX for some reason (perhaps it noticed something strange when it was moved to the new partition)
login: pam_unix(login:session): session opened for user root by LOGIN(uid=0)
login: ROOT LOG........
#solution
Edit /etc/yum.repos.d/openvz.repo
For the first two entries comment out #mirrorlist and uncomment #baseurl and then it worked
openvz yum problem Centos 6.5 cannot find file on mirror:
yum update
Loaded plugins: fastestmirror
Determining fastest mirrors
* openvz-kernel-rhel6: mirrors.ustc.edu.cn
* openvz-utils: mirrors.ustc.edu.cn
base ........
Iwas surprised to see that Linux Mint at the latest 17.2 version still has NO mdadm installer option, and worse the installer will not be able to create a proper booting environment even when you do install it.
How to setup mdadm in Linux mint LiveCD
sudo su
apt-get install mdadm
# partition as you need and then create your mdadm devices
# create your SWAP md0
mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sda1 /d........
sudo apt-get install zoneminder
[sudo] password for one:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
libuser-perl python-evince kdebase-apps kwrite unixodbc
libgnomeprint2.2-data python-soappy vgabios python-metacity hddtemp
python-mediaprof........
rsync -Phaz --exclude=/dev/* --exclude=/sys/* --exclude=/proc/* --exclude=/mnt/md126 / /mnt/md126........
yum -y install wget
wget -P /etc/yum.repos.d/ http://ftp.openvz.org/openvz.repo
rpm --import http://ftp.openvz.org/RPM-GPG-Key-OpenVZ
yum -y install vzkernel vzctl
#enable ip_forward
sed -i s/'net.ipv4.ip_forward = 0'/'net.ipv4.ip_forward = 1'/g /etc/sysctl.conf
#all interfaces should not send redirects
echo "net.ipv4.conf.default.send_redirects = 1" >> /etc/sysctl.conf
echo "net.ipv4.co........
root (hd2,1)
Filesystem type unknown, partition type 0x83
grub> root (hd2,2)
root (hd2,2)
Filesystem type is ext2fs, partition type 0x83
grub> setup (hd2)
setup (hd2)
Checking if "/boot/grub/stage1" exists... no
Checking if "/grub/stage1" exists... no
#weird thing about grub is that the drive you enter is considered hd0
For example when booted fu........
Message from syslogd@server at Sep 14 11:35:59 ...
kernel:[Hardware Error]: MC4 Error (node 1): DRAM ECC error detected on the NB.
Message from syslogd@server at Sep 14 11:35:59 ...
kernel:[Hardware Error]: Error Status: Corrected error, no action required.
Message from syslogd@server at Sep 14 11:35:59 ...
kernel:[Hardware Error]: CPU:6 (10:8:0) MC4_STATUS[Over|CE|MiscV|-|AddrV|CECC]: 0xdc00400021080813........
Motherboard: Gigabyte GA-3CESL: http://b2b.gigabyte.com/products/product-page.aspx?pid=2658#dl
Dell Part Numbers for the motherboard: R1232 R1232L R2232S SERVER MOTHERBOARD GENUINE 408P9 CN-0408P9
GA-3CESL Manual Download here
RAMSlots: 16 (8 controlled by each CPU)
RAMType: DDR2 ECC 5300P........
This happened while trying to delete several thousand users from phpBB and basically corrupted the innoDB tables.
InnoDB: Page lsn 3 881164362, low 4 bytes of lsn at page end 881164362
InnoDB: Page number (if stored to page already) 86920,
InnoDB: space id (if created with >= MySQL-4.1.1 and stored already) 0
InnoDB: Page may be an index page where index id is 700
InnoDB: (index "tid_post_time" of table "phpBBdb2005"."phpbb3_p........
[ 17.208336] tg3 0000:08:00.0: eth0: Link is up at 1000 Mbps, full duplex
[ 17.210194] tg3 0000:08:00.0: eth0: Flow control is on for TX and on for RX
[ 76.000065] phy0 -> rt2x00lib_request_firmware: Error - Failed to request Firmware.
[ 76.002332] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[ 86.736004] eth0: no IPv6 routers present
[ 148.960038] phy0 -> rt2x00lib_request_fi........
It is a permissions issue that is hard to fix.
All but one USB device is greyed out.
I am already a member of "vboxusers"
I have already enabled and disabled USB support for the guest.
I have already reinstalled the latest VBOx guest editions
If running as root it all works fine
Changing........
libguestfs tools howto guide for managing virtual machine images.
libguestfs-tools aka guestfs tools has a lot of tools that make this very easy for you. You can easily mount partitons from an image with some of the commands below.
To mount a partition
#mount the kvmuser102821.img image and the /dev/sda1 partition from it to the local directory "mount"
guestmount -a kvmuser102821.img -m /dev/sda1 mount
........
cc: Internal error: Killed (program cc1)
Please submit a full bug report.
See for instructions.
make: *** [ext/fileinfo/libmagic/apprentice.lo] Error 1
make: *** Waiting for unfinished jobs....
Stopping crond: ........
i337 Canada on Bell is hard to root or even install TWRP
Installed TWRP from Odin and my computer gave me the bluescreen at the end but it seemed to be successful (after ODIN said reset).
TWRP mode does not seem to enter, instead you get the Android recovery mode with Volume up + Home
http://galaxys4root.com/galaxy-s4-root/how-to-root-att-or-verizon-galaxy-s4-on-android-4-4-2/
1.)........
First of all if you're getting this error it is a result of extreme database activity. If you aren't expecting it or it doesn't make sense to you 99% of the time this is a database driven script being exploited (some common examples I see often are things like phpBB being hit by dozens, hundreds or thousands of bots making constant DB write requests).
The easiest way to identify this is to restart MySQL and then run the third party tool "mtop" and you'll see all........
iptables -t nat -A PREROUTING -p tcp -m tcp -d 192.168.2.1/32 --dport 3389 -j DNAT --to-destination 192.168.5.2:3389
iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.
The above is often because you don't have the correct modules loaded on the hostnode or enabled for the container but in some cases it's actually a weird openvz setting.
Che........
Aug 25 16:43:24 evohostingtor postfix/master[19471]: fatal: /etc/postfix/master.cf: line 24: field "unprivileged": bad value: "???"
Solution: I had the wrong thick dashes when c&ping (just retype them with your keyboard)
Aug 25 16:47:10 mailbox postfix/master[24498]: fatal: /etc/postfix/master.cf: line 25: bad transport type: syslog_name=postfix/auth-cleanup
auth-cleanup unix n - - - 0 cleanup
#-o syslog_name=postfix/........
CPanel says you can access 98% of the functions through CLI which experienced Unix/Linux admins prefer for simplicity and for scripting. I've never found CPanel easy to use from the admin panel, it seems everything is hard to find and a simple task becomes a series of hunts.
So for people like me here's the list: http://cpanel.net/system-administrators/command-line-scrip........
Dial ****
Then 110#
It will then say what your current IP address is.........
Many may ask why would you need to do this? When upgrading from phpBB 2 to 3 the conversion does not keep the admin user you create. If your old admin user has an email address associated that no longer works or is accessible this makes it impossible to reset the admin password.
Some may just say "I'll just manually edit the e-mail address" but it won't work and phpBB will fail to find that user if you don't update the "user_email_hash" field but how do........
To first start off, there are many misconceptions about NoSQL and especially its strengths and weaknesses.
Even the popular NoSQL solution MongoDB is fraught with issues that no one seems to be concerned about aside from a few but there are serious issues with database integrity and verified writes. MySQL was considered dangerous or incomplete at one point without having the transactional safety features of Oracle for example.
However the NoSQLimplementations seem........
Enter the console as root
mysql -u root -p
Then kill the process (where 1234 = the thread ID)
kill 1234
It's also a good idea to use a tool like "mtop" to monitor which processes and queries are slow, killing them is a temporary fix while you try to isolate the actual problem.........
It is located in /root/.my.cnf
This is truly a horrible idea and a security flaw and on top of that MySQL port 3306 is wide open by default with CPanel.........
This is what fixed it:
[root@box13 ~]# dd if=/dev/zero of=/dev/md160 bs=512 count=500
Basically you need to wipe out more than just the 512 byte partition table so 512 bytes * 500 is more than enough to make DRBD happy and think the partition is now empty.
The reason this happens is because it gets confused when there is a previous partition with data on the device you are using.
root@box13 ~]# d........
I used the matching 8.3.13 utilities and it didn't work but strangely the newer 8.3.16 which makes DRBD complain works just fine.
GIT-hash: 83ca112086600faacab2f157bc5a9324f7bd7f77 build by root@sighted, 2012-10-09 12:47:51
0: cs:SyncSource ro:Secondary/Primary ds:UpToDate/Inconsistent A r-----
ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:5236960
&am........
#count=10000 makes an image of 10000MB make sure your image is at least the same as your existing
dd if=/dev/zero of=yourimage.img bs=1M count=10000
# losetup -fv newimage.raw
# fdisk -cu /dev/loop0
# kpartx -a /dev/loop0
# dd if= of=/dev/mapper/loop0p1
# e2fsck -f /dev/mapper/loop0p1
# resize2fs /dev/mapper/loop0p1
# a lot of guides tell you to edit /etc/fst........
lvextend -L +10G /dev/kvmvm/w2k8r2evalstandard
Extending logical volume w2k8r2evalstandard to 20.00 GiB
Logical volume w2k8r2evalstandard successfully resized
The above adds 10GB to the logical volume. Of course you must resize the filesystem using other tools to take advantage of the space.........
This problem seemed to happen recently but was likely causing issues before where the phone(s) do not ring.
Now there are a few reasons why this can happen especially if your adapter has DND mode enabled (disable it).
However that wasn't my issue and Ionly figured it out the other day when by fluke if you're on the phone (making a call) then calls will come in.
That's when Ifigured out the solution:
This likely app........
yum -y install wget
wget -P /etc/yum.repos.d/ http://ftp.openvz.org/openvz.repo
rpm --import http://ftp.openvz.org/RPM-GPG-Key-OpenVZ
yum -y install vzkernel vzctl
After that just reboot and you may also have to enable ip_forward in /etc/sysctl.conf........
root@hkhosting [/]# service httpd start
Starting httpd: Syntax error on line 2 of /etc/httpd/conf/httpd.conf:
Invalid command 'Alias', perhaps misspelled or defined by a module not included in the server configuration
........
I never found a solution to do it live (nothing worked that I found) so it looks like a relogin is required.
Check your maximum file limit
cat /proc/sys/fs/file-max
824460
This is different than your actual's user limit which you'll see below
ulimit -n
1024
Try and set it higher but it won't work
ulimit -n 65000........
It's not as simple as "yum install" as you can see below and it doesn't stop there.
yum install php53
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* rpmforge: mirror.us.leaseweb.net
* extras: centos.mirror.rafal.ca
* updates: centos.mirror.nexicom.net
* base: centos.mirror.nexicom.net
* addons: centos.mirror.nexicom.net
Setting up Install Process........
[Wed Jan 08 18:50:07 2014] [emerg] (28)No space left on device: Couldn't create accept lock (/etc/httpd/logs/accept.lock.15449) (5)
This may happen when trying to restart Apache and you find it dies right after starting and check /var/log/httpd/error_logs.
What is the cause of this?
You could be out of disk space (if you're not then see #2 and below)
You're out of Semaphores, you need to kill all the old ones.........
ALTER TABLE yourtable ADD COLUMN info VARCHAR(255)........
Kernel panic - not syncing: Attempted to kill init!
Pid: 1, comm: init Not tained: 3.2.51-3.el6.x86_64 #1
Call Trace:
panic+0x8c/0x1a2
forget_original_parent+0x34d/0x360
exit_notify+0x12/0x140
do_exit+0x1d8/0x400
do_group_exit_+0x50/0xc0
sys_exit_group+0x12/0x20
system_call_fastpath+0x16/0x1b
panic occurred, switching back to text console........
This server has been running for weeks without issue, it's currently only using 1 of 2 CPUs as it is running in the office as a test bed (mainly due to the handle 12 bay storage/great for testing HDDs). The errors below seem to mainly be from AMD CPUs, it's only happened a single time and in the days since Igot that error it hasn't occurrred.
Interestingly enough /proc/cpuinfo still shows all 4 cores of the CPU (Opteron 2373 Quadcore HE) and the functionality doesn't seem........
service monit status
monit dead but subsys locked
........
All Errors (CPanel does not report by domain, but puts everything in a single log which Ithink is a bit silly and annoying):
/usr/local/apache/logs/error_log
Access_Logs
They are found within the home directory of the site user eg.:
/home/admin/access-logs/yoursite.com
MySQL Logs
/var/lib/mysql/yourhostname.err........
DELETE FROM `wp_comments` WHERE NOT comment_author_email IN ('user@hotmail.com','another@hotmail.com')
The above is an example of specific records you type out, but you could also base it on a subquery.........
./configure
./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc
yum -y install gcc make
./configure
./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc
yum -y install compat-gcc-*
./configure
Error: Could not find alsa
Make sure to have the alsa libs and headers installed.
yum -y install alsa-lib-devel
./configure........
This happens because of a permissions or ownership issue.
Generally /var/lib/mysql should be all owned by mysql.mysql (check that).
To fix it use chown -R mysql.mysql /var/lib/mysql
Also make sure the files are at least readable and writable by mysql (eg. 700).........
mount -o bind /proc /sda2/proc
mount -o bind /dev/ /sda2/dev
mount -o bind /sys /sda2/sys
chroot /sda2
mint / # mount -o bind /proc /sda2/proc
mint / # mount -o bind /dev/ /sda2/dev
mint / # mount -o bind /sys /sda2/sys
mint / # chroot /sda2
mint / # cd ~
mint ~ # ls
Desktop
mint ~ # cd /
mint / # ls
bin Desktop dev-temp home&nb........
Linux box13. 2.6.32-042stab076.5 #1 SMP Mon Mar 18 20:41:34 MSK 2013 x86_64 x86_64 x86_64 GNU/Linux
even setting privvmpages to a specific setting DOES not affect "free -m" in containers.
This is probably a kernel issue
23:36:29 up 159 days, 7:12, 4 users, load average: 0.42, 0.44, 0.33
[root@box13 ~]# free -m
total&n........
Sipura / Linksys PAP/VOIP/SIP Adapter Issue
Can't receiving incoming phone calls and you're behind a NAT router (99% of people)?
1. Login to the adapter.
2. Click on "Advanced" (location varies but usually somewhere on top)
2. Click on "SIP"
3. Scroll down to "NAT" (usually at the bottom).
You'll find 2 columns with 4 rows of drop-down boxes (they'........
Starting container...
vzquota : (error) Quota on syscall for id 42131: No such file or directory
vzquota on failed [3]
Solution
cd /var/vzquota
mv quota.42131 quota.42131-disable
vzctl start 42131
Starting container...
Initializing quota ...
Container is mounted
Adding IP address(es):
Setting CPU units: 1000
Container start in progress...
........
The units in echo are kB as in kilobyte.
Setting a high sync speed
echo 120000 >/proc/sys/dev/raid/speed_limit_min
This will increase the speed, note that sometimes a rebuild is slow due to current disk activity/iowait.
If that is not the cause then you may have a hardware issue (controller, cable or a bad drive).
Setting a lower sync speed
echo 1200 >/proc/sys/dev/raid/speed_limit_max........
service mysqld start
MySQL Daemon failed to start.
Starting mysqld: [FAILED]
mysqld_safe
cat /var/lib/mysql/server.err
130917 17:57:09 InnoDB: Started; log sequence number 0 0
13091........
PHP5 Centos 6 displays part of code from PHP file for some scripts
Solution
edit /etc/php.ini change short_open_tag = Off to:
short_open_tag = On
Then restart Apache and it should be resolved (assuming the scripts failing used )
........
/scripts/phpextensionmgr install PHPSuHosin
Updating md5sum list
Fetching http://httpupdate.cpanel.net/cpanelsync/easy/targz.yaml (connected:0).......(request attempt 1/12)...Resolving httpupdate.cpanel.net...(resolve attempt 1/65)...
Fetching http://httpupdate.cpanel.net/mirror_addr_list (connected:0).......(request attempt 1/3)......connecting to 74.50.120.123...@74.50.120.123......connected......receiving...100%......request success......Done........
The first is a dual CPU AMD Opteron 2373EE (4 cores x 2) and I think it did bad because it has some old 250GB SATAs which can only do about 65MB/s max sequential reads. I think it should have blown away the second (AMD X4 640 Quad Core).
[root@fs12home unixbench-4.1.0-wht-2]# ./Run
make all
make[1]: Entering directory `/root/unixbench-4.1.0-wht-2'
Checking distribution of files
./pgms exists
./src exists........
I just realized I have some blank users which I deleted butI can still login to this dummy account without a password for some reason.
mysql -u -p
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 5
Server version: 5.1.69 Source distribution
Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation an........
I've got one of these for testing projects from work at home and got more than I bargained for with the time I've spent on it due to the storage handing/Perc 6/i cards.
My particular model came with the following:
2U Rack Mount Server with Rails
2xOpteron 2373 EE (Quad Core, there is a 6-core version that can be found at times)
16GB RAM
2 x 250GB Seagate SATA
2 x Dell Perc 6/i (horrible and a nightmare to work........
One thing to remember is that you need MegaCli to do the flashing.
You also need the correct file,I tried at least 2 different Perc 6 firmwares from Dell that kept getting rejected as corrupt by MegaCli(they were really the wrong version). I have an external PCI-E Dell 6 Perc/I butI chose images from the 'Integrated" on motherboard version as it was allI could find. They are different, and below is my first time finding success.........
I flashed an LSI Logic firmware to it and it broke the BIOS (cannot do Ctrl+R) for booting purposes but allows other functionality to work normally.
I tried downgrading to a Dell firmware for Perc 6i but it won't work, not even with MegaCli
wget http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN
--2013-08-26 12:53:39-- http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN
Resolvi........
LSi Megaraid
At first it was configured as a RAID 0, then I deleted the Virtual Disk Group.
I thought both drives would be shown and detected in Linux as sda and sdb but it actually shows nothing.
To make them work you have to hit Ctrl+R before the system boots (when prompted) and create a Virtual Disk Group. In my case I created each one as RAID 0 (with a single drive only) as I just wanted JBOD but there is no such option or default in these Dell Pe........
pxe-32 tftp open timeout
The solution was to enable tftp in xinetd with "chkconfig tftp on".
See the troubleshooting below:
chkconfig --list
NetworkManager 0:off 1:off 2:off 3:off 4:off 5:off 6:off
acpid 0:off&n........
yum update error
Traceback (most recent call last):
File "/usr/bin/yum", line 29, in ?
yummain.user_main(sys.argv[1:], exit_code=True)
File "/usr/share/yum-cli/yummain.py", line 229, in user_main
errcode = main(args)
File "/usr/share/yum-cli/yummain.py", line 145, in main
(result, resultmsgs) = base.buildTransaction()
&nbs........
mkdir: cannot create directory 'test': Disk quota exceeded
You are out of inodes usually:
df -i
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/simfs 200000 200000 0 100% /
none ........
The error itself "mkdir(): Too Many Links" is not very useful, but I'll translate it into plain English.
It means you've reached the filesystem's limit of how many directories can be created in a single directory.
In this case for ext3 the limit is 32000 and it was exceeded.
What's the solution?
The simple solution is to move those directories into more subdirectories possibly sorting them by date, alphabet or numerically.........
This is a great way to test and experiment without risking your current table, or to make a backup of your current table to avoid corruption or dataloss due to malicious activity eg. deletion etc..
There are two steps and two commands
1.)Copy Table Structure
"cars_backup" is the new table and it will be a copy of the table called "cars"........
SELECT column_name
FROM information_schema.columns
W........
Jun 12 10:30:53 kernel: [724514.291670] EXT4-fs error (device md20): ext4_add_entry: bad entry in directory #2552670: rec_len % 4 != 0 - offset=216, inode=2553603, rec_len=94, name_len=84
Jun 12 10:30:53 kernel: [724514.292400] EXT4-fs error (device md20): ext4_add_entry: bad entry in directory #2552670: rec_len % 4 != 0 - offset=216, inode=2553603, rec_len=94, name_len=84
This happened when an unprivileged user was backing up a Windows filesystem, once they ha........
Image -> Mode -> RGB........
This is just trying to read 5GB off the drive with dd and the drive initially tested ok but shortly after I wondered why I was seeing 2MB/s read speeds. Notice the "current_pending_sector", anytime I've seen it at anything above 0 even with no other bad fields/attributes, it means the drive is bad.
ata1.00: exception Emask 0x0 SAct 0x3 SErr 0x0 action 0x0
ata1.00: irq_stat 0x40000008
ata1.00: failed command: READ FPDMA QUEUED
ata1.00: cmd 60/00:00:........
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
bind-address=127.0.0.1
The key is "bind-address", set that to 127.0.0.1 and no one from outside the server can connect.........
mysqldump: Couldn't execute 'show create table `general_log`': SHOW command denied to user 'user'@'localhost' for table 'general_log' (1142)
One of my clients almost found out the hard way, here is an unlikely situation that happened.
1.) Years ago the client had another VPS to which they backed up a BLOG nightly to an .sql file, what they forgot is that the file also contained all databases (they used the --all-databases option but forgot). So imagi........
flush privileges;
ERROR 1146 (42S02): Table ‘mysql.servers’ doesn’t exist
This happened to me on a system running Centos with the REMI repo and a new version of Mysql 5 (which the official Centos/RHEL does not support on version 5).
The solution is just to run this program "mysql_upgrade", after that flush privileges will work.
mysql_upgrade........
mysql -u username --password='yourpassword' ........
This is useful for developing a lot of applications, I'm putting it here to keep it handy for myself and hopefully others:
Choose CountryCanadaJapanUnited StatesUnited KingdomAfghanistan........
On occassion and from a variety of networks and clients, Sent messages don't get saved.
I'm wondering if these log messages could be why:
May 3 14:16:39 mail.box postfix/smtpd[5195]: connect from 192.168.1.58
May 3 14:16:39 mail.box postfix/smtpd[5195]: SSL_accept error from 192.168.1.58: -1
May 3 14:16:39 mail.box postfix/smtpd[5195]: lost connection after CONNECT from 192.168.1.58
May 3 14:16:39 mail.box postfix/smtpd[5195]:........
service mysql start
Starting MySQL. ERROR! Manager of pid-file quit without updating file.
Solution
killall -9 mysqld_safe
killall -9 mysqld
service mysql start
Starting MySQL SUCCESS!........
If you make changes to /etc/sysctl.conf (which are permanent and not lost during reboot) but want them to apply with rebooting just use the following command:
sysctl -p
After that your changes will be enabled.........
smartctl -a /dev/sda
smartctl version 5.36 [i686-pc-linux-gnu] Copyright (C) 2002-6 Bruce Allen
Home page is http://smartmontools.sourceforge.net/
Device: ATA WDC WD1600YS-01S Version: 20.0
Serial number: WD-WCAP03024940
Device type: disk
Local Time is: Mon Apr 29 21:40:07 2013 PDT
Device does not support SMART
Error Counter logging not supported........
If you move your hard drive(s) around to other computers/servers, you'll find that your eth0 keeps getting higher, the first time it will become eth1 and then eth2 etc and even higher if your server has dual or quad NICs. The reason is that udevd basically assigns eth0 tot he first NIC it finds and remembers it, if it encounters a NIC with a differentMAC, it assigns it one higher (eg. eth1).
See the example below, I have eth2 now so how doI fix it?........
Client Log
OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to 192.168.1.253 [192.168.1.253] port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
debug1: identity file /root/.ssh/identity type -1
debug1: identity file /root/.ssh/id_rsa type 1
debug1: identity file /root/.ssh/id_d........
Kernel panic - not syncing: Attempted to kill init!
Pid: 1,comm: init Tained: G I------------- 2.6.32-358.el6.x86_64 #1
Call Trace:
[] ? panic+0xa0/0x16f
[] ? do_exit+0x862/0x870
[] ? fput+0x25/0x30
[] ? do_group_exit+0x58/0xd0
[] ? sys_exit_........
This is a handy link and list of all the relevant Directadmin log files and related servers.
http://help.directadmin.com/item.php?id=11
DirectAdmin:
/var/log/directadmin/error.log
/var/log/directadmin/errortaskq.log
/var/log/directadmin/system.log
/var/log/directadmin/security.log
Apache:........
cat | grub --device-map=/dev/null
Now pay close to the attention of the beginning.
Type: "device (hd0) VPS.img" this is telling what hd0 will be to GRUB and we're telling it the disk image file "VPS.img" in the current directory is hd0, you can specify alternate paths and image names of course.
GNU GRUB version 0.97 (640K lower / 3072K upper memory)
[ Minimal BASH-li........
This booting error is because the Xen PV guest image uses the Xen kernel, this is not compatible with anything but a host running a Xen kernel.
I did a kpartx -av virtual.img and then it created some partitions that showed up in fdisk.
I mounted it and did a chroot into it and removed the xen kernel and installed a normal kernel but Xen still shows the same kernel in Grub (only the Xen one).
This is strange but it seems like this Xen PV guest has some sort of hidden or........
I closed program by program untilI found the culprit, it's baffling how the cause was Thunderbird but then again it does use a lot of memory and I have thousands of messages between dozens of mailboxes.
But still I don't think this should happen and Xorg shouldn't allow this either.
So for those who have mysteriously high CPUusage from Xorg start closing program by program until you find the culprit.
The interesting thing is that after reloading it, the Xor........
Inever started these processes but they are from a custom based bootable Linux I've made and I've never seen this behavior on other machines or even with the same machine using different kernels. These processes seemed to spawn on their own and I have no idea why and even worse why the CPU usage is so high?
Here's the output from top:
907 extaudit 30 10 0 0 0 R 90.7 0.0........
Let's keep this simple, it's horrible, not only is the picture quality horrible (it's not a big deal) but the keyboard input is an issue. You have to type slowly, lightly and carefully otherwise 1-keystroke could end up being dozens of keystrokes.
It's also a confusing unit for many datacenter techs, I've seen these units hooked up wrong and the instructions themselves aren't clear. I had to resort to shipping one to my office and take my phone pictures of the setup for th........
arp -a
syst (192.168.1.122) at 21:96:43:3a:62:a2 [ether] on eth0
arp -d 192.168.1.122
If you get an error do:
arp -d 192.168.1.122 -i eth0
Sometimes the arp cache just won't clear either, some say it should automatically but there are cases where the above doesn't work. I believe it may be that some network applications are keeping the entry alive but this is just a guess.........
df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg_12-lv_root
50G 1.2G 46G 3% /
tmpfs 7.8G 0&nb........
This is something I often setup for clients because it's very helpful for people in datacenters, this allows custom OS installs on demand, you can customize it more by using kickstart etc.. but here's a base I use before customizing more:
This little script below will install everything you need to get booting by PXE Linux.
It also assumes you set a local IP (be sure not to overwrite your existing IP) on eth0:0 (note the :0) as 192.168.1.10 and it........
This seems to be common for some reason when trying to run Windows 7 under KVM and 7 has always had strange issues with KVM. What happens for me is after the install it simply won't boot, it stays on the POST screen and does nothing.
For some reason it appears the boot sector either doesn't get installed or gets corrupted with KVM.
The solution is to boot the install disc for Windows 7 and reinstall the windows MBR into the boot sector:
1. Boot t........
ip_conntrack: table full, dropping packet.
A lot of clients I've seen have this issue, it really seems the default level is way too small. Once this connection tracking table becomes full then packets get dropped which is obviously a bad thing.
One thing to be mindful of though is that 350 bytes of memory are used per entry so there is some justification for not keeping it too high. However, if you have multiple servers running or high traffic daemons........
I backed up everything in the /mnt/sd_card directory thinking that some dataloss could occur for some reason but purposely left my microSDHC unbacked up thinking that "it won't touch that since it's external" and Samsung's and other manufacturers website even say this (that it won't be affected and not to worry etc).
Apparently I was wrong, my microSD was "undetected" and asked to be formatted after the upgrade (there goes 3-months worth of family photos). No........
This may sound silly but there will be conflicts/issues with the default Centos repository so you have to use a third party like remi (I prefer not to do this but it's the only option unless you migrate your sites/data to another server or can stand some downtime-not an option IMHOon a production server).
You may need to upgrade to PHP5.3 to run Joomla or many other reasons.
Your host needs to use PHP 5.2.4 or higher to run this version of Jo........
The best way I could figure out is to use another guest of some sort to do this, while assigning the disk that needs to be resized to the same guest.
So say we have /dev/xvda as the guests drive and we've booted it up.
We also have /dev/xvdb (this is going to be the image/disk to be resized).
In this case it's based on an ext3/4 image.
Run e2fsck on it to ensure there are no filesystem errors.
e2fsck /dev/xvdb........
ERROR 1045 (28000): Access denied for user 'contentmanager'@'localhost' (using password: YES)
For fun I thought I'd reset the password:
GRANT ALL ON thecontent.* TO contentmanager IDENTIFIED by 'dfdfsdfdsfsdfsd';
ERROR 1470 (HY000): String 'contentmanager' is too long for user name (should be no longer than 16)
This is ridiculous that this new version has some bizarre 16 character username limit and not only that but i........
CREATE TABLE articles_backup LIKE articles
The code above creates a new table called "articles_backup" which has the exact same structure and attributes as the original articles table.
CREATE TABLE articles_backup SELECT * FROM articles;
The above code does the same thing as the first example, BUT it also copies all of the data.........
Error: detected vswap CT config but kernel does not support vswap
This means either old kernel or bad config (physpages NOT set to 0:unlimited)
Solution
vzctl set $veid --physpages 0:unlimited --save........
iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?)
This solution applies to all other iptables modules/problems for OpenVZ, you'll just need to add them to both lists/lines below if you have modules other than what I have below.
The modules need to be enabled in both iptables and the OpenVZ hostnode itself and then the containers which need it must be restarted.
How To Enable IPTables Modules in OpenVZ........
For years I've always built cheap systems believing that there is little difference in more expensive components when it comes to reliability and quality, I generally believe this still except for Power Supplies.
I've always bought cheap cases with nice sounding 350-550W stock/cheap/crap power supplies and haven't had any issues for the most part until recently.
One such case is an NGEAR case with a 550W Optimax power supply, I always read that these supplies don't produce the........
I'm running Ubuntu 10.10 with Asus NVIDIA GT430
2.6.35-32-generic-pae #65-Ubuntu SMP Tue Jan 24 14:06:16 UTC 2012 i686 GNU/Linux
Nvidia binary driver: 260.19.06
The screen sometimes completely freezes and locks up or everything starts going very slow:
[1903398.100007] NVRM: os_schedule: Attempted to yield the CPU while in atomic or interrupt context
[1903402.373210] NVRM: Xid (0001:00): 53, CMDre 00000000 00000080 00000000 00000005 00........
fdisk -lu VPS.img
last_lba(): I don't know how to handle files with mode 81ed
You must set cylinders.
You can do this from the extra functions menu.
Disk VPS.img: 0 MB, 0 bytes
255 heads, 63 sectors/track, 0 cylinders, total 0 sectors
Units = sectors of 1 * 512 = 512 bytes
Device Boot Start End ........
I dread updating the kernel and rebooting to find the Ubuntu graphics aren't working and you have to manually intervene. This is usually because Ubuntu for whatever reason didn't update the drivers you need (eg. the manually compiled Nvidia Kernel driver that MUST be recompiled for each and every kernel update unfortunately).
The most common reason may be that "linux-source" hasn't been installed automatically on my system. I tried to manually reinstall the........
This is one in a series of weird things whichIthought was motherboard related (I RMA'd the motherboard), the RAM tests fine with memtest86 and I used badblocks on both RAID 1 members with no errors and smartctl is happy with them.
Basically the array crashes the kernel a lot and has issues when writing.
[112322.723465] md0: rw=0, want=14958668696, limit=1887460480
[112322.731077] attempt to access beyond end of device
[112322.731087] md........
This is the mail system at host mail.postmail.com.
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
&........
PDOException: SQLSTATE[42000] [1044] Access denied for user 'db_user'@'localhost' to database 'dbname' in lock_may_be_available() (line
167 of /home/user/public_html/includes/lock.inc).
The username and password were correct but some reason CPanel added the user with no permissions! Edit the user's permissions to include "All" from Cpanel or MySQL and that is the solution.........
These were caused by a bad stick of Corsair RAM
[] free_hot_cold_page+0xfc/0x150
[] __pagevec_free+0x14/0x1a
[] release_pages+0x127/0x12f
[] __pagevec_release+0x15/0x1d
[] __invalid_mapping_pages+0x120/0x156
[........
It's actually fairly straight forward:
load data local infile 'billpayments-payments.csv' into table payments
fields terminated by ','
enclosed by '"'
lines terminated by 'n'
The above assumes that your fields are terminated by a comma (some programs like OpenOffice change this to a semi-colon ;) and that they are enclosed with "
The above will insert the data from billpayments-payments.csv into the table payments.........
The normal solution would be as follows:
export DISPLAY=:0.0
/usr/lib/vino/vino-server &
But what happens if that doesn't work? I haven't been able to find much documentation about how to find the list of displays and how their numbering works in Xorg.
Sometimes you'll get this error when trying to restart vino:
Cannot open display:
For some reason my display is not on 0.0........
I'll start by showing some problems in the logs:
[2011/08/07 16:22:06, 0] param/loadparm.c:8569(process_usershare_file)
process_usershare_file: stat of /var/lib/samba/usershares/movie failed. Permission denied
[2011/08/07 16:22:06, 1] smbd/service.c:676(make_connection_snum)
create_connection_server_info failed: NT_STATUS_ACCESS_DENIED
That means you don't have permission to access the fi........
I had a system running a 128MB live CD image with 2.8 gigs of available RAM and the OOM kernel killer went crazy when using dd for more than 8 minutes and kept killing everything. I've read that this is due to a low-memory issue and paging in the kernel and 32-bit systems with lots of RAM.
I even enabled swapspace on my LiveCD and the issue happened 25 minutes into dd rather than 8 minutes, so what gives?
Also no swap space was ever used!
cat /proc/s........
I like dd, although it only reads it, usually a read test of the entire disk will uncover if your hard drive is bad in some parts. This is a good thing to do at least once a month, a lot of times bizarre program behavior, laginess and crashing/unnmounting problems etc.. are due to a failing disc and SMART won't know it or indicate a problem:
We must also remember there's never a guarantee, I've found that ever since we moved to larger and more platters per drive with 1TB drives........
It's weird because I have a nearly identical box and setup and I can update the ovzkernel-PAE* just fine but on this box it doesn't work.
I only get this error with the openvz.repo and not others such as Centos-Base.repo
With my other server it works normally:
================
Setting up Update Process
Resolving Dependencies
--> Running transaction check
---> Package ovzkernel-PAE.i686 0:2.6.18-238.12.1.el5.0........
GNU GRUB version 0.97 (640K lower / 3072K upper memory)
[ Minimal BASH-like line editing is supported. For the first word, TAB
lists possible command completions. Anywhere else TAB lists the possible
completions of a device/filename.]
grub> root (hd1,0)
Filesystem type is ext2fs, partition type 0xfd
grub> setup........
I thought only a faster CPUand SSDwould help but I already have a Quad-Core CPU and it wasn't being maxed out. The actual tests were performed on an AMD-V enabled 128MB dual core VMWare container though.
There is a flag that can be passed to make in order to start multiple threads, by specifying 4 threads I was able to reduce the whole kernel compilation time from scratch by about 50%! (65minutes vs 31minutes!). *Yes I did do a make clean before each co........
Timeout error occurred trying to stop MySQL Daemon.
Stopping MySQL: [FAILED]
[root@devbox stats]#
Solution (force kill mysqld - warning you do risk table corruption here but there's no choice i........
If you have a webserver and find you have high IO/lagginess MySQL is one of the first things to check. It turns out MySQL was my problem and it was creating a high load on my server, especially for IO.
How to Enable MySQL Slow Query Logging To Find Slow Performance/Queries
vi /etc/my.cnf
Add this anywhere under [mysqld]
#slow queries
log-slow-queries = /var/log/mysql/mysqlslowqueries.log
long_query_time = 1........
yum -y install vnstat
chown nobody.nobody -R /var/lib/vnstat/
#replace venet0 below with your desired interface
sudo -u nobody vnstat -u -i venet0
#edit: vi /etc/sysconfig/vnstat
#VNSTAT_OPTIONS="-i venet0"
# only use the sed below if you are using venet0 instead of eth0 or replace accordingly
sed -i 's/eth0/venet0/g' /etc/sysconfig/vnstat
[root@monitor]# yum install vn........
mysql errors even though these files do exist:
110405 13:21:37 InnoDB: Operating system error number 13 in a file operation.
InnoDB: The error means mysqld does not have the access rights to
InnoDB: the directory.
InnoDB: File name ./ibdata1
InnoDB: File operation call: 'open'.
InnoDB: Cannot continue operation.
110405 13:26:15 InnoDB: Operating system error number 13 in a file operation.
InnoDB: The error means my........
drup 6.2 install
$cd drupgoodinst3883/
[ drupgoodinst3883]$ ls
CHANGELOG.txt cron.php index.php INSTALL.pgsql.txt INSTALL.txt MAINTAINERS.txt modules robots.txt sites update.php xmlrpc.php
COPYRIGHT.txt includes INSTALL.mysql.txt install.php LICENSE.txt misc&........
I don't expect this to be solved soon but some of Yahoo's DNS servers are out of whack. I changed the IPs of some nameservers of some domains and now most Yahoo users can't e-mail to those domains!
As you can see below by the "No MX or A records for mychangedomain.com", now Yahoo's DNS/mailserver DNS cache is wrong. You would think they would at least have cached the old incorrect records, but instead for some reason their DNS cache has no entry and doesn't seem........
high IO wait
424 root 39 19 1900 848 552 D 0.0 0.0 0:00.91 updatedb
root 424 0.0 0.0 1900 848 ? DN Mar11 0:00 /usr/bin/updatedb -f sysfs?rootfs?bdev?proc?cpuset?binfmt_misc?debugfs?sockfs?usbfs?pipefs?anon_inodefs?futexfs?tmpfs?inotifyfs?eventp........
kernel 2.6.27.54
Fusion MPT base driver 3.04.07
Copyright (c) 1999-2008 LSI Corporation
Fusion MPT SPI Host driver 3.04.07
mptbase: ioc0: Initiating bringup
mptbase: ioc0: WARNING - Unexpected doorbell active!
mptbase: ioc0: ERROR - Doorbell ACK timeout (count=4999), IntStatus=80000001!
mptbase: ioc0: ERROR - Diagnostic reset FAILED! (102h)
mptbase: ioc0: WARNING - NOT READY!
mptbase: ioc0: ERROR - didn't initialize proper........
Centos 5 Postfix and SPAMASSASSIN Tutorial
yum install spamassassin
chkconfig spamassassin on
vi /etc/mail/spamassassin/local.cf
##############
#required_hits 5
#report_safe 0
#rewrite_header Subject [SPAM]
#5 is the least restrictive (means only the most obvious SPAM is caught. 0 is obviously the most restrictive/sensitive and would have lots of false positives
require........
When migrating away from Plesk I couldn't figure out an easy way to get a straight list of all e-mails, but here is where I found the solution:
http://nakuls77.wordpress.com/2008/08/30/details-of-email-ftp-database-users-from-psa-database/
mysql> SELECT mail.mail_name, accounts.password, domains.name FROM mail, accounts, domains WHERE domains.id=mail.dom_id AND mail.account_id=accounts.id;
mysql> SELECT CONCAT(mail.mail_name,’@’,domains.name) AS Em........
don't delete /var/lib/mysql/ib_logfile0 or ibdata1 or mysql won't restart
I didn't realize they were internal and not part of replication like the relay files!
/usr/libexec/mysqld: ready for connections.
Version: '4.1.22-log' socket: '/var/lib/mysql/mysql.sock' port: 3306 Source distribution
110127 16:31:00 [Note] /usr/libexec/mysqld: Normal shutdown
110127 16:31:00 InnoDB: Starting shutdown...........
sshd[9217]: Authentication refused: bad ownership or modes for file /root/.ssh/authorized_keys
I made sure the entire .ssh subdir is owned by the user root (this is root's account);
chown -R root.root .ssh
chmod 600 .ssh/authorized_keys
but it still doesn't work and gives me the same message
sshd[7339]: Authentication refused: bad ownership or modes for directory /root
chmod 700 /root........
Affected rows: 0
Warning: #1264 Out of range value adjusted for column 'deleteon' at row 1
SQL query:
UPDATE `custtable`.`custinfo` SET `deleteon` = '2011-02-29 00:00:00' WHERE `custinfo`.`custid` =105 LIMIT 1 ;
This happened after a migration to a new SQL database due to user error. The old database server MySQL 3.23 or 4 allowed an impossible date to be entered by a user. As we know February 29th DOESNOT exist but the database al........
Basically you should always be 100% sure that whatever IPyour mail server sends out with has reverse DNS/PTR records. Remember that unless you own your IPs then you won't be able to set your own reverse DNS. Even if you were to create a reverse PTR record on your DNS servers it will be ignored. Reverse DNS is queried to pre-assigned DNS servers of your ISP, so therefore you'll need to contact your ISP/Colo/Hosting provider to do a reverse DNS entry.
If you don't have........
Many people aren't aware but recently Dual-Master Replication setups have become increasingly popular. That's because you get similar features and benefits of having a full-blown cluster (difficult to setup and maintain and requires I believe 3 servers just as controllers).
With a dual-master you just have a different off-set for the keys and you should be good, but of course there is the chance that at some point replication will halt because of an unexpected or unforseen error........
I think this will be useful to others because I have a server that kept crashing mysteriously during intense disk usage/RAID checks. It would only crash during the weekly RAID integrity check.
ThenI noticed during a reboot that not all CPUs were being brought up, as a result this actually creates much higher temperatures with the output I got from sensors, just booting the system produced higher than normal temperatures.
You can imagine that a full blown RAID check........
understanding /etc/aliases
*remember to apply changes you need to run "newaliases" after editing /etc/aliases
one thing I don't get is that it doesn't allow you to specify the whole e-mail address on the left-hand side
eg:
yourfullemail@domain.com: someotheremail@domain.com
postalias: warning: /etc/aliases, line 109: name must be local (if you try the above)
It works more like this:
your........
mysqldump does not include CREATE DATABASE statement
you need the --databases option
"--databases" is misleading, it implies in the documentation that this is a list of databases to be dumped, it should be clear that uses this command in conjuction with dumping a single database also adds CREATE DATABASE and is the only way to get the database to automatically create itself.........
Jan 16 04:02:03 centosbox syslogd 1.4.1: restart.
Jan 16 04:07:34 centosbox kernel: INFO: task updatedb:20771 blocked for more than 300 seconds.
Jan 16 04:07:34 centosbox kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jan 16 04:07:34 centosbox kernel: updatedb D F78BE050 6476 20771 20766&n........
CPU/Kernel/MB/RAID problem?
Jan 5 12:45:05 testbox kernel: [653298.890004] BUG: soft lockup - CPU#0 stuck for 61s! [hal-acl-tool:4168]
Jan 5 12:45:05 testbox kernel: [653298.890005] Modules linked in: vmnet vmci vmmon binfmt_misc drbd video output input_polldev ocfs2_stackglue ocfs2_dlmfs ocfs2_dlm ocfs2_nodemanager configfs k8temp hwmon_vid lp snd_hda_intel snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi........
I found the cause of this issue was from all the diskspace being used but clearing it was not enough. Iguess the tables became inconsistent when space ran out and myisamchk is what fixed the rest.
service mysqld restart
ERROR! MySQL manager or server PID file could not be found!
....................................................................................... ERROR! Manager of pid-file quit without updating file.
se........
PHP Fatal error: Call to undefined function mysql_connect()
yum install php-*........
mysqldump --all-databases > allDB.sql
The above dumps ALL the mysql databases to "allDB.sql".
If you want to compress with gzip you could do this instead:
mysqldump --all-databases > gzip > ALLDB.sql.gz........
Virtualmin Postfix Error:
The status of your system is being checked to ensure that all enabled features are available, that the mail server is properly configured, and that quotas are active ..
A problem was found with your Postfix virtual maps : No map sources were found in the Postfix configuration
.. your system is not ready for use by Virtualmin.
........
This made me nervous but it's clearly a cronjob based on the messages log that happens every Sunday at about 4:22.
I actually can't find any evidence of it in cron.d cron.daily but it is there somewhere obviously.
What I don't get is why doesn't this cronjob do a datacheck like Ubuntu's cronscript does? When you unnecessarily rebuild the array you lose your redundancy during that point which makes your data extremely vulnerable.
*Update I did a grep of &q........
I can't tell if it's Flash or Javascript that they were using, but it basically caused my sysetm to lockup until I closed that one page. Is this proof enough that Wal-mart is evil?:)
I've never seen that before, it's weird how certain things mask themselves as high CPU usage with Xorg, unless it is some kind of weird Xorg problem but I believe it's more of a Flash/Javascript issue from Firefox in Wal-mart's evil scripting.........
This doesn't seem to be widely known (maybe it's in some documentation that none of us read though)but there's an easy way to check the integrity of any mdadm array:
sudo echo check > /sys/block/md0/md/sync_action
-bash: /sys/block/md0/md/sync_action: Permission denied
sudo will never work, this only works as root since echo is not actually a binary/command. It is built-into bash.
/sys/devices/virtu........
Install the "Editors" and "Net" groups that will give you rsync, ssh, ssh-keygen and cron.
The trickiest thing that I keep forgetting about each time is you have to run "cron-config" which adds the cron service to Windows, and without doing that obviously no cron jobs will be run thus making automatic backups impossible.
Warning about rsync/cygwin and using the -a archive switch.
It's a good thing I caught this because it doesn't work ri........
This really made me nervous but notice the mdstat says "check". This is because in Ubuntu there is a scheduled mdadm cronscript that runs everyday on Sunday at 00:57 that checks your entire array. This is a good way because it prevents gradual but unnoticed data corruption which Inever thought of.
As long as the check completes properly you have peace of mind knowing that your data integretiy is assured and that your hard drives are functioning properly (I'........
mdadm: metadata format 00.90 unknown, ignored.
This happens with various versions of older mdadm such as mdadm - v2.6.7.1 - 15th October 2008
It is all because an extra 0 in 00.90 in /etc/mdadm/mdadm.conf that it doesn't like (it doesn't seem to cause any problem except that message though):
Solution - Edit your /etc/mdadm/mdadm.conf and change 00.90 to 0.90 in your arrays:
ARRAY /dev/md3 level=raid1 num-devices=2 metadata=0.90 UUID=f41a4644:6b2a05f........
One of the purposes of rsync is to backup whole filesystems and archive them but how can you do that properly and restore things to normal if all permissions and ownerships are not preserved from your root filesystem?
It's not desirable to have everything running as root, especially not just for an rsync.
The Easy rsync preserve permission solution for non-root users
sudo is the answer and all you have to do is edit /etc/sudoers
At the end o........
I've only used it on Centos, soI thought I'd make a quick Debian guide:
Install the DRBD Package
apt-get install drbd8-utils
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
libswfdec-0.8-0
Use 'apt-get autoremove' to remove them.
The following........
yum exits in the middle
The problem is this VPS seems to be an OpenVZ template from HyperVM. The only way to make it work was to disable i386 packages since this was an x64 kernel. That shouldn't be necessary but it was the only way to make yum stop quitting after the first package or two. I couldn't find any issue by checking the logs either.
echo y|yum install vim-minimal telnet expect jwhois net-tools slocate iptables elinks gawk
L........
I separated the 2 drives in the RAID 1 array.
1 is the old one /dev/sda and is out of date, while the separated other one /dev/sdc was in another drive and mounted and used with more data (updated).
I wonder how mdadm will handle this:
usb-storage: device scan complete
md: md127 stopped.
md: bind
md: md127: raid array is not clean -- starting background reconstruction
raid1: raid set md127 active with 1 out of 2 m........
Nov 29 20:17:58 ubuntu kernel: [ 1157.180789] md: md1 stopped.
Nov 29 20:17:58 ubuntu kernel: [ 1157.180829] md0: unknown partition table
filesystem not responding/reading properly with du or rsync (this needed an fsck).
[ 2571.489217] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923106
[ 2571.942299] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923110
[ 2571.9568........
Moving to RAID was a pain.
What you have to do is the following from an existing install:
Install mdadm
Create your mdadm RAID 1 array on your spare hard drive.
Start it with the missing disk.
rsync the entire contents of your current / to the md partition.
Here's a good way of doing it:
rsync -Pha --exclude=/proc/* --exclude=/sys/* --exclude=/mnt/* /. /mnt/md2........
From a LiveCD or if you're doing something like converting your non-RAID install to mdadm here's how you would chroot properly (you have to mount your proc, sys and dev on the running system/LiveCD to your chroot environment if you want things to work right, especially if you need to run update-initramfs due to a driver change etc..)
*replace "path" with your mount/chroot path
mount -o bind /proc /mnt/path/proc
mount -o bind /dev/ mnt/pa........
ping test.com
connect: No buffer space available
/var/log/messages
Oct 18 12:21:03 vps kernel: printk: 177 messages suppressed.
Oct 18 12:21:03 vps kernel: Neighbour table overflow.
Solution in /etc/sysctl.conf:
net.ipv4.neigh.default.gc_thresh1 = 4096
net.ipv4.neigh.default.gc_thresh2 = 8192
net.ipv4.neigh.default.gc_thresh3 = 8192
net.ipv4.neigh.default.base_reachab........
service vz start
Starting OpenVZ: failed to load module vzmon [FAILED]
vzmon: Unknown symbol ve_snmp_proc_init
vzmon: Unknown symbol addrconf_sysctl_free
vzmon: Unknown symbol ve_ndisc_init
vzmon: Unknown symbol addrconf_ifdown
vzmon: Unknown symbol ip6_frag_cleanup
vzmon: Unknown symbol fini_ve_route6........
service vz start
Starting OpenVZ: failed to load module vzmon [FAILED]
vzmon: Unknown symbol ve_snmp_proc_init
vzmon: Unknown symbol addrconf_sysctl_free
vzmon: Unknown symbol ve_ndisc_init
vzmon: Unknown symbol addrconf_ifdown
vzmon: Unknown symbol ip6_frag_cleanup
vzmon: Unknown symbol fini_ve_route6
........
cd /etc/yum.repos.d
wget http://download.openvz.org/openvz.repo
rpm --import http://download.openvz.org/RPM-GPG-Key-OpenVZ
yum install ovz-kernel-PAE
Now remember to set /etc/sysctl.conf to "net.ipv4.ip_forward = 1"
You can apply the change immediately by running sysctl -w net.ipv4.ip_forward = 1 but remember that you still have to set sysctl.conf
sysctl -p will load and apply any changes to s........
Remember to replace "eth0" with your NIC device although usually it will be eth0.
Replace 192.168.1.1 with your default gateway, remember you can also add multiple gateways by adding a second/different default gateway.
route
Kernel IP routing table
Destination Gateway Genmask&nb........
Always make a backup of the original file before trying this, I find this kind of thing when updating IPs etc.. to use a script.
Where the old IP is "192.168.5.8" and the new IP is "10.10.5.8"
sed -i s/192.168.5.8/10.10.5.8/g testdomain.org.db
The -i with sed means "inline" meaning we edit the file directly, but without the -i we could just use >and output the results to another file or do whatever else we wanted.........
Create New RAID 1 Array:
First setup your partitions (make sure they are exactly the same size)
In my example I have sda3 and sdb3 which are 500GB in size.
mdadm --create /dev/md2 --level=1 --raid-devices=2 /dev/sda3 /dev/sdb3
mdadm: array /dev/md2 started.
Check Status Of The Array
*Note I already have other arrays md0 and md1.
You can see below that md2 is syn........
Virtualbox Error
I tried to copy a .vdi of one container to use in another one, basically to clone instead of having to install the OS again.
Failed to start the virtual machine Centos 5.5 Mirror.
Medium '/home/testuser/.VirtualBox/HardDisks/Centos 5.5 Mirror.vdi' is not accessible. UUID {a1a9fad7-0402-4867-b8f3-39fb49454bc5} of the medium '/home/testuser/.VirtualBox/HardDisks/Centos 5.5 Mirror.vdi' does not match the value {4945a0e8-0ed5-4736-9088-bcaf........
I am a huge fan of Linux and the idea of OpenSource but I've said it many times, there are still hurdles in today in 2010 for Linux as a Desktop. Linux is still intended for servers at its very core. This can be changed succesfully though, as Apple has shown us with Mac OS X based on FreeBSD.
Half of the issue is lack of driver support and the other half is the Linux Kernel and Window Manages, KDE and GNome still both don't cut it (but they're getting closer).
I'll........
Different distributions such as Debian and Centos behave differently when trying to shutdown your system.
shutdown -H now on Debian does not do what you'd expect. The system won't power down, it will halt and do everything but power down.
shutdown -PH now will do the job though (actually power the system off). This is important to test especially if you are not near the system. If you just use -P it forcefully shuts off which is not........
This error is annoying, in a Virtuozzo KB entry about this ip tables nat problem they say the kernel needs to be ugpraded:
Symptoms
The node runs 2.6.18-x kernel older than 2.6.18-028stab053.10.
NAT module does not work in container, you get "can't initialize iptables table 'nat'" error:
# iptables -t nat........
For a standalone system the solution is simple, just use the same version of Windows a copy a good version of:
C:windowsSecurityDatabasesecedit.sdb from another computer.
Then you should be able to login again without getting the nasty message "Local policy does not permit you to log on interactively."
Of course you will probably need a way of accessing the filesystem off-line in order to get to it such as a Linux boot disc.
Some........
md: Autodetecting RAID arrays.
md: autorun ...
md: considering sdb1 ...
md: adding sdb1 ...
md: adding sda1 ...
md: created md0
md: bind
md: bind
md: running:
md: kicking non-fresh sda1 from array!
md: unbind
md: export_rdev(sda1)
raid1: raid set md0 active with 1 out of 2 mirrors
The md0 raid kicked sda1 ou........
http://www.tomshardware.com/news/RAID-5-Doomed-2009,6525.html
I found this article interesting, it basically says that with 2TB hard drives or larger sizes, you are more likely to encounter an unrecoverable read error. But is this just another Y2K doomsday? Don't HDD's have enough advanced hardware ECC error and read recovery to prevent this from happening?
I'm almost tempted to build a 3 x........
This is a great way to reduce MySQL code/mistakes/annoyance when doing things, take for example this statement:
INSERT IGNORE INTO sometable(CatName) VALUES("someitem");
Notice the "IGNORE", that is what does the magic.
Normally if the entry "someitem" existed you'd get an error message back such as "Duplicate entry for whatever". What I have normally done in PHP or whatever language is manually coded or made a........
This is a great way to use your ftp server space, for example on your web hosting account (althoughI believe many hosts don't allow storage like this), but if you have a VPS/Dedicated Server etc.., this would be perfect. Imagine how easy it is to work with an ftp account that you can just mount as a normal partition or directory in Linux, it would be great for backups etc..
Name
curlftpfs - mount a ftp host as a local directory
Synopsis........
*Note OS X is strange to install, I thought my HDD was not being detected by you just have to go to Diskutil and create a partition for the root filesystem and then close/move the Window and proceed with the install.
After install Mac OS X 10.4.6 Tiger I get a black screen that says:
b0 error
Most people say the partition has to be marked as "active", actually that just means marked as "bootable". Instead of t........
This is based on Debian Linux but should apply equally to any *nix distro.
Install LUKS/crypt-setup
apt-get install cryptsetup
Setup your LUKS Partition
Of course change /dev/md2 with whatever partition you intend to use LUKS on.
cryptsetup --verbose --verify-passphrase luksFormat /dev/md2
You'll be asked to verify your decryption password twice
*DO NOT FORGET THIS PASSWORD AS IT IS NOT RECOVERABLE!........
My XBOX's dashboard/firmware was from sometime in 2008 when I first bought the system. I mainly played using composite cables but at my brother in law's house we used HDMI. The very first time it worked, but then I bought some games that did some update and after that HDMI never worked.
The symptoms besides having on sound is that your XBOX will show PC monitor resolutions but won't have any option to say you have a 720P or 1080P display, this means the XBOX firmware is fa........
Why would you want to downgrade the superblock? Old mdadm verisons like mdadm 2.5.6 only use the 0.90 superblock/metadata and new versions use 1,1.0,1.1 and 1.2 superblocks by default.
There are some annoying caveats with this, first of all the new superblocks (later than 0.90) CANNOT be read by GRUB, so you won't even be able to install GRUB. Even worse, old versions of mdadm CANNOT automatically detect arrays even if they were created with a new version of mdadm with th........
route add -net 192.16.5.0 netmask 255.255.255.0 eth0
Of course adjust as you need (eg. the 192.16.5.0 should be changed to the subnet you need access to and eth0 should be changed to the network device that you want that subnet routed through). I also use the /etc/sysconfig/rc.local script and add the above into it (remember that this route only gets added AFTER all other init scripts have finished though).........
I wasted a lot of time wondering why I could never find those packages.
Check the /etc/yum.conf file and at the bottom look for the "exclude=" line.
Below is what I found in mine
exclude=apache* httpd* mod_* mysql* MySQL* da_* *ftp* exim* sendmail* php* bind-chroot*
Just remove those entries or uncomment that line and you'll get access to the missing applications.........
Basically the two main types of distros are Debian and RHEL/Centos based. I'm just going to give a quick overview of how the configuration of IP interfaces works in Debian/Centos based distros.
*Just one thing to remember, when setting IPs statically you have to manually specify a DNS server in /etc/resolv.conf (since DHCP is what normally does it automatically)
Debian/Ubuntu/Kubuntu/MEPIS
The IP (DHCP &........
The default options for iptables are very basic. Here is what you need to do in order to enable them in OpenVZ.
1.) Add the modules to iptables and restart iptables:
vi /etc/sysconfig/iptables-config
Edit the line as so:
IPTABLES_MODULES="ipt_REJECT ipt_tos ipt_TOS ipt_LOG ip_conntrack ipt_limit ipt_multiport iptable_filter iptable_mangle ipt_TCPMSS ipt_tcpmss ipt_ttl ipt_length ipt_state iptable_nat ip_nat_ftp"
2.........
One note is to secure MySQL, I don't know for sure but I believe you could login to MySQL remotely with no password during this operation (I'm not sure, maybe it doesn't accept blank passwords but I firewall MySQL port anyway and recommend you do the same).
First edit /etc/my.cf
Under the [mysqld] field add the following line somewhere:
skip-grant-tables
Now restart mysql: service mysql restart or on Debian sty........
I successfully created a single RAID 1 partition which includes /boot inside it and my root directory through the Debian installer. It said GRUB installed successfully but when I try booting the OS it seems GRUB can't read anything.
When trying to boot from GRUB
GRUB Loading stage 1.5.
GRUB loading, please wait...
Error 2
I get "Error 2" when trying to boot Debian. I also notice from a LiveCD that........
I installed 5.5 with a 300GB RAID 1 partition (boot is also on this partition). It booted up fine the first few times until after I used a Live CD and accessed the array, and it became named /dev/md127 for some reason.
Now whenI boot into CentOS I get a kernel panic and different errors, once I got "invalid superblock", even though the array is fine (it didn't happen again, probably because I was sure to dismount and stop the mdadm array properly).
Here's what........
This function and others may not work with the stock PHPinstall on Centos/CPanel: Fatal error: Call to > undefined function imagecreatefromjpeg()
Even with libjpeg-devel installed it won't work because PHP was not compiled with jpeg support, so we have to do the dirty work ourselves :)
Here is the command/yum's I did to install missing libraries for PHP that configure will complain about (yes it is a one by one process).
yum install bzip2-........
This was unbelievable how much the Xen kernel slows things down, keep in mind both tests were done on the hostnode, one was with the Openvz-Xen hybrid kernel and the other was just OpenVZ. You can see the performance difference is nearly 300% better when not using the Xen kernel.
OpenVZ-Xen Kernel Test Results (I was wondering what was wrong/so slow with my Core i5!)
# # # # # #&n........
It's not just as simple as running the chroot command, you need to ensure the /proc and /dev entries are passed through and populated to the chroot environment.
Step 1 - Mount Your Off-lineOS
mount /dev/sda1 /mnt
Step 2 - Mount Proc
mount -t proc none /mnt/proc
Step 3 - Mount Dev
Most guides will tell you to use this: mount -o bind /dev /mnt//dev but that doesn't work for some reason in many cases:
mount: wron........
This is a very simple solution, but most guides out there make you login twice (once to scp the key) and once to put the key in authorized_keys. There's no need for that.
If you don't already have a ~/.ssh/id_rsa.pub just type "ssh-keygen -t rsa" and keep hitting enter until it's done :)
Just use this code to easily enable passwordless login with SSHD
key=`cat ~/.ssh/id_rsa.pub`;ssh user@192.168.5.25 "echo $key >> ~/.ssh/auth........
Out of memory: kill process 7559 (rsync) score 635 or a child
Killed process 7559 (rsync)
I was surprised to see this in my dmesg whenmy rsync backup suddenly stalled/stopped.
This system has 3 gigs of RAM and lots of free memory so I don't understand what is happening.
rsync invoked oom-killer: gfp_mask=0x200d2, order=0, oomkilladj=0
Pid: 7600, comm: rsync Not tainted 2.6.24.2 #83
[] oom_kill_pr........
Not sure what rsync switches/options to use?
rsync -PDrphogtl
The short version would be:
rsync -Pha
I think these are really common sense options to use and probaby should be the default.
Explanation of rsync switches
P = display the progress
D = hybrid of --specials and --devices so all special and device files will be copied as well.
r = recursive (otherwise rsync won't copy files deeper than........
I thought there would be an error message or warning from MySQL in the case that the text you submit is greater than the allowed limit based on the field.
So essentially I submitted text that was about 120,000 characters long, whereas the limit of TEXT is just 65,535 characters! I almost lost half of my data/what I typed without knowing it!
I just altered the field type in my database from TEXT to LONGTEXT. I can't see how LONGTEXT wouldn't be long enough for MOST........
From the package "parted" you can use the command "partprobe" to re-read the partition table. I really hate rebooting, and that's what Iloved to hear about AHCI motherboards, that they allow hotswap so you don't have to reboot. But that's only as good as the OS, if the OS does not reload the partition table you won't be able to do anything with that new drive you attached without rebooting. Yes, even without re-reading the partiton table Linux will........
Before we start I take no responsibility for this, you should have a backup and if you make a mistake during this process you could wipe out all of your data. So backup somewhere else before starting this as a precaution, or make sure it's data you could afford to lose.
The RAID 1 Setup (Hardware Wise)
I've already setup my 2 x 1TB (Seagate) drives with identical partitions, make sure your new hard drive (the empty one) is setup like your curr........
The binary "iostat" comes from the package "sysstat" and is available on all Linux/Unix like platforms.
Use the "-m" option to give you what you probably want, which is to see in MB/s how much bandwidth each disk is doing.
iostat -m
Linux 2.6.24.2 ((none)) 04/16/10
avg-cpu: %user %nice %system %iowait %steal %idle
........
I have no idea why but mkfs.ext3 defaults to a patheticlly small blocksize of 1024 bytes/1KB (kilobyte). That means the maximum filesize is ONLY 16GB! With 2KB/2048 bytes you get a 256 GB maximum filesize, and with 4KB/4096 bytes you get 2TB!
I finally noticed/paid attention to this after realizing that with rsync and scp that no file larger than 17GB could be transferred. I then realized it must be a file size limit on the partition.
Here is what tune2fs tol........
The folder I was trying to archive is about 72GB, but much like rsync at about 17GB it chokes because of the filesize. What's with so many common and essential Linux tools having such limitations? I guess it is likely that the authors never wrote their code with the idea that files would be so large but it's still very annoying. It's important to stay on top of these limitations on production servers because I didn't realize what happened until I checked the file with "........
The last transfer I was able to do was 16.77GB according to rsync's output and it worked fine.
16.77G 100% 10.66MB/s 0:25:00 (xfer#17484, to-check=234753/256249)
But on a file over 17GB (gigs) it stalls. Trust me, it really is stalled, it's been about 8 hours with no progression from that point for some reason.
17.24G 54% 10.65MB/s 0:22:07........
I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find.
yum search ftp
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* rpmforge: ftp-stud.fht-esslingen.de
* base: mirrors.netdna.com
* updates: updates.interworx.info
* addons: yum.singlehop.com
* extras: mirrors.netdna.com
rpmforge........
Here are the results, it is Sempron 3000+ AMD Mobile, 500Gig HDD, 512MB RAM with shared ATI Radeon graphics.
# # # # # # # ##### ###### # # #### # #
# # ## # # # #&nb........
PHP cannot access /usr/bin/opensslI have verified the username that runs the process is able to access /usr/bin/openssl and it does exist but the PHP script is saying it doesn't exist:
[code:1:1fd0f3abbe]
if (!file_exists($OPENSSL)) {
//echo "ERROR: OPENSSL $OPENSSL not foundn";
}[/code:1:1fd0f3abbe]
I don't get itI can clearly see the contents of /usr/bin by using the PHP system fu........
GRUB Boot FreeBSD[code:1:a7050277b7]title FreeBSD 6.0
root (hd0,2,a)
kernel /boot/loader[/code:1:a7050277b7]
Just insert the above code into GRUB's [b:a7050277b7]menu.lst[/b:a7050277b7] and make sure you set the root path correctly.
[quote:a7050277b7]Let's quickly explain what the root (hd0,2,a) means:
*hd0 stands for the primary master drive
*2 stands for partition 3
*a stands for the........
SSH automatic login without passwordlocal> ssh-keygen -t rsa -f .ssh/id_rsa
-t is the encryption type
-f tells where to store the public/private key pairs. In this case, the .ssh directory on home is being used
A password will be asked; leave this part blank, just pressing
Now, go the .ssh directory, and you will find two new files: id_dsa and id_dsa.pub. The last one is the public part. Now, copy the public key to the serv........
Mount Linux ext2 file systemNormally in Linux you could mount ext2 or ext3 etc... like this:
mount -t ext2 /dev/hda1 /mnt/hda1/
In FreeBSD the difference is of course the disk naming conventions (hda1 would be known a /dev/ad0s1):
To mount ext2 in FreeBSD just type:
mount -t ext2[b:68c16c60bf]fs[/b:68c16c60bf] /dev/ad0s1 /mnt/ad0s1........
Asterisk FreeBSD compile problemsI couldn't get it to compile without using the following options at compile time:
[b:b7d672ee28]
make install WITHOUT_ZAPTEL=YES WITHOUT_MYSQL=YES WITHOUT_FAX=YES WITHOUT_ODBC=YES WITHOUT_H323=YES[/b:b7d672ee28]Some problems you might have with copying over your Linux config files to FreeBSD is different paths.
[b:f044931f41]For example the etc path for Asterisk on BSD will now be:[/b:f044931f41]
[qu........
Problems surfing web/servingI noticed sometimes websites wouldn't load at random through a FreeBSD box and other systems on the same link didn't have the issue. I believe it is because of the low default limit of 128 TCP connections that caused the problem. It would also slow down any traffic that requires many connections such as Bittorrent.
The fix is to increase the amount of connections to at least 1024
Edit [b:520b050d3e]/etc/sysctl.conf[/b:520b05........
CREATE Database/Granting PrivilegesCREATE your first database
Code:
[code:1:0668cd8e74]CREATE database myfirstdb;
[/code:1:0668cd8e74]
CREATE a user for your first database
This one creates the user 'sqladmin' and gives them 'usage' on your new database 'myfirstdb'
Code:
[code:1:0668cd8e74]mysql> GRANT usage on myfirstdb.* to sqladmin@localhost;
Query OK, 0 rows affected (0.00 sec)[/code:1:0668........
Setup Static IP Address ONBOOTAssuming you are using eth0
Note this will work for any version of CentOS and basically any version of Redhat Linux or Redhat based distribution.
You would need to create a new file
[code:1:02f8d34c30] /etc/sysconfig/network-scripts/ifcfg-eth0:0[/code:1:02f8d34c30]
DEVICE=eth0:0
the ":0" at the end specifies alias 0 we could actually change this to ":99" or "........
Updated to Version 3.8 and can't loginSSHD accepts my password but then hangs at "Last login: Wed Sep 13 21:30:02 2006 from"
This occurred during a yum update after upgrading my release, installing the new kernel and rebooting.
I got kicked out of sshd after seeing the following during yum update:
telnet 100 % done 85/476
tux 100 % done 86/476
ntsysv 100 % done 87/476
rpmdb-redhat 94 % done 88/476........
/usr/bin/ld: cannot open crt1.o: No such file or directory[quote:812bec9db7]/usr/bin/ld: cannot open crt1.o: No such file or directory
collect2: ld returned 1 exit status[/quote:812bec9db7]
This is annoying and in my case it happened on Centos AMD 64 when compiling a 32bit program with GCC.
Install glibc-devel.i386 (make sure you get the i386 version and not the native 64 bit version which is likely already installed).
The joys of 3........
SSH Public Key Authentication (Login Without Passwords)I've gone over this before but just a quick note!
the "authorized_keys" file in ~/.ssh
must be chmodded to "600" or public key authentication won't work.
I guess it's kind of a security/failsafe feature that I've
seen on all Linux and Unix OS's........
Vonage & Linksys Offer Trade-In ProgramVonage & Linksys Offer Trade-In Program
Monday, June 13 @ 09:22:36 PDT
Vonage is offering customers a way to get a free 802.11g router when they turn in their old one.
advertising
For a limited time, customers can trade-in their used router any brand, any model for a Linksys Wireless-G Router with 2 Phone Jacks for broadband telephony (WRTP54G) for free (after rebates), when they si........
Intel's Finnish FetishIntel's Finnish Fetish
By Dave Mock
June 13, 2005
Chipmaker Intel (NASDAQ: INTC) has successfully topped the personal computer market for decades. Breaking into related areas such as communications has been much difficult for the world's largest semiconductor maker. But a new partnership with Nokia (NYSE: NOK) could help to change that.
Intel's forays into cellular-phone and home-entertaiment-device chips have........
Intruder detection device uses behavioural analysisIntruder detection device uses behavioural analysis
by Antony Savvas
Monday 13 June 2005
Symantec is introducing a new intrusion detection product that uses behavioural analysis to block potential attacks on enterprise networks.
The new Critical System Protection 4.5 system uses technology that Symantec acquired through last years purchase of Platform Logic. It is designed to protect deskt........
MySQL Server wouldn't startStart MySQL Server with the following script that would have installed with the port.
/usr/local/etc/rc.d/mysql-server.sh start........
MySQL root passwordWhen I installed MySQL I didn't set a root password nor do I know what it is![/b]........
MySQL Server 3.23 won't start after switching from 4.1I was using a 4.1 alpha version of mysql-server and some how version 3.23 of the client and 4.1 of the client were also both installed!
So I forced uninstalled everything because after trying and trying even though MySQL server was using the short 16byte password authentication I got some other errors.
After trying with the ports and having it fail because I had existing database data I force installe........
Backup Shell Script[quote:aaa4b0b165]#!/bin/sh
date=`date -I`
mysqldump --all-databases | gzip > /var/backup/backup-$date.sql.gz
[/quote:aaa4b0b165]
Something like that could be useful as a cronjob to locally or remotely backup your databases........
MySQL Reserved Wordshttp://dev.mysql.com/doc/mysql/en/reserved-words.html
You should familiarize yourself with these because you will have unexpected results if you use any of them.
Eg. try creating a table with what you think is valid syntax like this:
CREATE Table Order(
.......);
The word 'Order' is a reserved word and used to ORDER the results so you will get a syntax error from this one and you would think everything is........
MySQL SELECT with multiple where conditionsI can get a match on rows for now apparent reason
[quote:09cf04e097]SELECT * FROM TABLE WHERE field = 'value' & value = 'field'
[/quote:09cf04e097]
To make it work as expected use 'AND' instead of '&' they seem to have a completely different and unexpected effect.
[quote:09cf04e097]SELECT * FROM TABLE WHERE field = 'value' AND value = 'field'
[........
MySQL SubQueryI was trying to do a sub-query here but it wouldn't work (Syntax Error) in MySQL for some reason even though based on the SQL standards it should be ok.
[i:1268bfa39e][b:1268bfa39e]I found the reason this doesn't work. I am using MySQL 3.23 and I read on the MySQL web site that versions before 4.1 DO NOT SUPPORT SUB-QUERIES so it showed me how to rewrite the following as a LEFT join instead of a sub-query.
[/b:1268bfa39e][/i:1268bfa39e]........
Create Table with structure of another existing tableOk, this has many valid uses such as if you need to create backups or the ability to undo changes, you would want to create new tables with the same structure as another. Here is how you do it.
[i:7ed9581493]
Also remember Indexes such as PRIMARY KEYS [b:7ed9581493]will not be preserved[/b:7ed9581493] so you will have to readd them manually.[/i:7ed9581493]
[code:1:7ed9581493]CREATE TABLE NewName AS SEL........
sed is great for pattern matching or retrieving linesHere is a cool example
Say you type df:
The output would be something like:
[quote:3bb8d51437]Filesystem 1k-blocks Used Available Use% Mounted on
/dev/hda2 1712432 1206664 418780 75% /
/dev/hda1 31201 10505 19085 36% /boot
none 30932 0 30932 0% /dev/shm
[/quote:3bb8d51........
Basic Port ListingHopefully someone finds this useful or at least interesting.
http://www.sans.org/top20/#u9
Name Port Protocol Description
Small services ........
Other Security Web SitesSeveral websites actively track security issues. This list provides you with the major providers
of security information on the Web. Many of these organizations also provide newsletters and
mailings to announce changes or security threats:
Center for Education and Research in Information Assurance and Security (CERIAS)
CERIAS is an industry-sponsored center at Purdue University that is focused on technology and
relate........
Clustering LinksI thought this might be interesting for people with spare time.
[b:6423c19973]Great clustering article from Linux Mag[/b:6423c19973]
http://www.linux-mag.com/2003-11/clusters_01.html
[b:6423c19973]General Linux cluster information[/b:6423c19973]
http://www.gdargaud.net/Hack/ClusterNotes.html#HighA
http://www.faqs.org/docs/Linux-HOWTO/Cluster-HOWTO.html#s3
http://www.yolinux.com/TUTORIALS/LinuxClustersAndFileSys........
InnoSetup is something Ijust realized many commercial developers use for installation. Why? Because it's100% FREE, simple, and efficient to use.
The maker has really done a great job and the installer basically works on all versions of Windows since 95.
I'll keep this in mind the next time I code a Windows application since it's been years for me.........
I played around with xmit power (how much power in mW) to see if I could increase the range and signal strength. Idon't think this Linksys WRT54G's strength is the wireless, it seems to have poor signal quality and transfer rates all around.
Ithink part of the problem is also that there are several wireless networks around my house that could be interfering and the walls are thick here.
Anyaway, moving on now :) The default is 28mW and I increased it to........
Linux Kernel v2.6.30.3
102220 blocks
CHK include/linux/version.h
CHK include/linux/utsrelease.h
SYMLINK include/asm -> include/asm-x86
CALL scripts/checksyscalls.sh
CHK include/linux/compile.h
CC drivers/net/igb/igb_main.o
drivers/net/igb/igb_main.c: In function `igb_up':........
This happened with a select statement which writes the result to an external file. I didn't remember the privilege "FILE" must be granted on *.* for this to work successfully, it wasn't actually an authentication issue as it implies since I was already in the SQL prompt and doing the query.
SELECT some_id
FROM sometable
INTO OUTFILE '/tmp/result.txt'........
I've gotten this error enough to bother posting about it, because I've come across so many servers where this happens, so what could "Error 28" possibly mean? Is your database corrupt, or is this a sign of a RAID failure/corruption or even worse, bad blocks on a clients system who has no RAID and never took backups?
No, check your free blocks, it simply means you have no space. This was the result of a script that was overzealous and backed up the entire database........
top - 09:34:12 up 2 days, 20:57, 2 users, load average: 1.83, 1.99, 2.03
Tasks: 59 total, 2 running, 57 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.3%us, 0.0%sy, 0.0%ni, 0.0%id, 99.7%wa, 0.0%hi, 0.0%si, 0.0%st
That 99.7% wa is iowait, it means the server is waiting for a process to complete an IOoperation or in plain English, there is a delay in........
100215 07:02:24 mysqld started
/usr/libexec/mysqld: Can't read dir of '/tmp/' (Errcode: 13)
/usr/libexec/mysqld: Can't create/write to file '/tmp/ibyP1qUC' (Errcode: 13)
100215 7:02:24 InnoDB: Error: unable to create temporary file; errno: 13
100215 7:02:24 [ERROR] Can't init databases
100215 7:02:24 [ERROR] Aborting
100215 7:02:24 [Note] /usr/libexec/mysqld: Shutdown complete
100215 07:02:........
I wanted to disable the "Administrator" account for security purposes and Iread some "guide" on the internet that recommended that we run "C:WindowsSystem32sysprepsysprep.exe /generalize". I also clicked the option for "Generalize" and the computer rebooted and gave some OOBE error and restarted, and now I get the error above no matter what.
I read that some drivers such as ones from AVIRA AV can cause this because they're unsign........
Everyone says there is a "manual" way of doing it and then they tell you to use iTunes, but if you're like me, you're travelling on business in a foreign country and your laptop does not have iTunes and you don't have a way of getting it and/or don't want it.
For this example I'm using the provider "du" in Dubai, UAE (United Arab Emirates) but this method works for virtually all providers.
The requirements in this case to truly "manually update........
This is something that happens a lot and it is very dirty, as you probably know each site is hosted on a certain IP address. Sometimes a domain is hosted by a single IP address and the IP address defaults to this very same domain.
This means that if someone buys domain abcd.com and enters your IP address (the one of your website) as the A record, your content will show up on their domain as if it was their own.
There is an easy way to prevent this by using .htacces........
You can see the problem below, GRUB recognizes my hard drive and sees the partitions but cannot access them. This is from the GRUB boot disc I'm using.
What happened is that I had some power issues causing this system's power to be interrupted several times and basically an on/off on/off situation.
The system won't boot, I just get a flashing cursor and no message or error from GRUB. Obviously the problem is that my MBR seems corrupt or some other issue.
My........
The results are still not flattering and are nothing close to native performance. Unless GlusterFS has a "DRBD-like" option to delay writes over the network and to only read from the client side, I don't see how performance can ever improve much more.
After doing some client optimizations Iadded more to the score:
Start Benchmark Run: Sun Nov 29 00:37:44 PST 2009
00:37:44 up 3 min, 1 user, load average: 0.01........
I've tried to find a good sensible solution to cluster with and each technology has it's pros and cons and there is no perfect solution and I've found a lot of "exaggerations" in the applications, benefits and performance of these different filesystems.
DRBD
I first started off with DRBD and Ihave to say it does live up to the hype, is quite reliable (although it can be annoying to match up the kernel module and user applications since they must match and whe........
You might remember my original GluserFS/OpenVZ benchmark which produced a horrible 29.8
This is the exact same system, but using the latest 2.0.8 (with some small files patch which speeds up performance) you can see it is about 25% faster.
I also haven't tuned my config files at all, but there are some settings that should increase performance on small files which I believe i........
Loaded plugins: fastestmirror
rpmdb: mmap: No such device
error: db4 error(19) from dbenv->open: No such device
error: cannot open Packages index using db3 - No such device (19)
error: cannot open Packages database in /var/lib/rpm
Traceback (most recent call last):
File "/usr/bin/yum", line 29, in ?
yummain.user_main(sys.argv[1:], exit_code=True)
File "/usr/share/yum-cli/yummain.py&qu........
Itried everything Icould think of, and of course even with the NIC enabled in the BIOS nothing was working. The light would flash when you plugin the cable for a second, but that's all.
Due to another issue I'm about to post about (server is not compatible with 1TB/1000Gig Hard Drives), I updated the BIOS. I didn't even know the 100mbit NICs were not working untilI decided I should test each NIC one by one.
Inoticed that only 1 server out of........
This is very disappointing since GlusterFS markets itself as a solution to deploy VPS servers on. On the HNitself I get a Unixbench of about 360.
I'm also using an SSH tunnel to secure the communications, but even before that, things seemed very slow.
# # # # # # # #####&n........
In those 4 simple commands you can setup mutual key exchange between two sshservers by using a single login shell session and single window.
*Just change the IP address examples of (10.10.0.2) to the target of your mutual key exchange. It doesn't matter if the server is on a LANor WAN(well unless the server is behind a firewall and you cannot SSHinto it).........
A VPS Server I had just wasn't working right, code that I migrated there just wasn't working. For example, it kept telling me the connection to the database was unsuccessful, halfway through iterating through results it already had.
Then I realized it wasn't my code. Ichecked my /proc/user_beancounters and found this:
cat /proc/user_beancounters
Version: 2.5
uid resource held maxheld barrier limit failcnt........
Backing MySQL Databases
Backing Up/Dumping All Mysql Databases To A Single File
mysqldump --all-databases -u admin -p > allmysqldatabases.sql
The "-all-databases" clause is pretty obvious isn't it? It means that it will backup all databases.
The "-u admin" means login using the user "admin", if you h........
This is something that annoys a lot of people, fortunately the Redhat style OS's are the most simple in this respect. I disagree that Debian's way makes sense, it is more of a hackish approach in how they implement iptables.
Anyway, for those who are using Redhat/Centos style OS's it is very simple.
Set your rules from the shell/command prompt and to save the iptables firewall rules so they are remember/loaded on boot just run this command:
service iptables........
Truly, the only way to unleash the capabilities and customization abilities of iPhone are to jailbreak, it's not just for hackers anymore.
A few days ago someone by the named of "geohot" released a single click application called "purplera1n", which does the entire operation smoothly and seamlessly.
In our case, the first time it went as far as "done, wait for reboot" on our Windows machine and for minutes we waited and saw the pic on the iPhone w........
The dmg format is silly and annoying to work with, why couldn't Apple stick with the .iso standard? Anyway, there's an excellent Linux and Windows based tool to convert it back to a normal .iso Image called dmg2iso
I'll only cover theLinux version although the Windows pre-built binary works the same way.
Download dmg2iso here for free (from the author's website)
It's just silly and doesn't make sense that Ubuntu doe........
I've had an old Blackberry for a few years and I was ready to spend some serious cash on a nice Nokia. I love the idea of the Linux based Symbian S60 OS, so I was looking at phones like the E63, E71 (both are basically the same, at least CPU/screensize although E71 is thinner, has a 3MP camera, has GPS, and has dedicated buttons to adjust the volume).
Then Iheard about the N97 and what a revolution it was supposed to be and it was even compared to iPhone.
To........
When trying to even cd or ls the mounted OCFS2 partition it crashes. Ithink this is a combination of VMWare Server's problem and the way I mounted and symlinked to it.
More than anything this shows the problem and lack of forsight with VMWare, but also that OCFS2 is easily crashed if you do strange things.
Output of /var/log/messages for OCFS2
Apr 10 15:57:45 localhost kernel: [84331.691258] Modules linked in: vmnet vmci vmmon ocfs2_stac........
There's a lot of information and guides on OCFS2 for RHELand Centos Linux but the package setup and configuration is slightly different and this has thrown some people off.
Installing OC2FS
You should install the following packages to get started:
apt-get install ocfs2-tools ocfs2console
Configure OC2FS
In RHEL/Centos the main configuration file is located in /etc/sysconfig/o2cb
However in Debian based Linux it is located........
This will give you the basic info needed to browse and connect to Samba shares from the command line. From the GUI of Gnome or KDE etc, it is pretty standard and straight forward. However, I've found very little guides on how to do it from the command line and if you're like me, a nerd who prefers command line for its simplicity and for remote use, this is the way to go.
First get a list of all the Samba/SMB shares on the target.
smbclient -L hostname........