yum update
Loaded plugins: fastestmirror, ovl
Determining fastest mirrors
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=container error was
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"
One of the configured repositories failed (Unknown),
and yum doesn't have enough cached data to continue. At this point the onl........
Sometimes users take their removal drives and unplug and replug them to test what happens during the failure of a disk. However, this breaks things quite badly due to the /dev/mapper in LUKS not coming back online due to it not being closed.
In other words, generally with non-encrypted drives the process is smooth but when encrypted you may want to follow a strategy like this:
We can see below that both disks are unavailable as they were physically remov........
convert-im6.q16: DistributedPixelCache '127.0.0.1' @ error/distribute-cache.c/ConnectPixelCacheServer/244.
convert-im6.q16: cache resources exhausted `/tmp/magick-27777Al6FGY7dhyKt10' @ error/cache.c/OpenPixelCache/3984.
convert-im6.q16: DistributedPixelCache '127.0.0.1' @ error/distribute-cache.c/ConnectPixelCacheServer/244.
convert-im6.q16: cache resources exhausted `/tmp/magick-277772Y_-pJnMdT2r1' @ error/cache.c/OpenPixelCache/3984.
convert-im6.q16: Distr........
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........
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........
How to check what kernel version you have/currently running?
uname -rm
5.4.0-91-generic x86_64
The above shows us that we are running 5.4.0-91-generic on the x86_64 architecture.
The safest way is to stick with the same flavor eg if you're on generic, and say on kernel 5.4.0 then it makes sense to follow what is below. However, if you are migrating or dual booting between newer hardware (eg. you got a........
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........
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........
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,........
If you are installing ta-lib for Python and get this error then you can normally solve it by manually getting the ta-lib source files and compiling.
tar -zxvf ta-lib-0.4.0-src.tar.gz
cd ta-lib;./configure;make;make install
Collecting ta-lib
Downloading https://files.pythonhosted.org/packages/39/6f/6acaee2eac6afb2cc6a2adcb294080577f9983fbd2726395b9047c4e13ec/TA-Lib-0.4.26.tar.gz (272kB)
&nbs........
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........
pip3 install requests
Traceback (most recent call last):
File "/home/user/.local/bin/pip3", line 7, in
from pip._internal.cli.main import main
ModuleNotFoundError: No module named 'pip._internal'
As a quick and temp fix call the OS installed python and not the user .local/bin installed pip3
/usr/bin/pip3 install requests
Collecting requests
Cache e........
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........
Just use apt-cache policy to find the repo of a package:
apt-cache policy lxd
lxd:
Installed: 3.0.3-0ubuntu1~18.04.2
Candidate: 3.0.3-0ubuntu1~18.04.2
Version table:
*** 3.0.3-0ubuntu1~18.04.2 500
500 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 Packages
&nb........
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 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........
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........
yum update
Loaded plugins: fastestmirror
Setting up Install Process
Determining fastest mirrors
YumRepo Error: All mirror URLs are not using ftp, http[s] or file.
Eg. Invalid release/repo/arch combination/
removing mirrorlist with no valid mirrors: /var/cache/yum/x86_64/6/base/mirrorlist.txt
Error: Cannot find a valid baseurl for repo: base
You have mail in /var/spool/mail/root
........
kdenlive is VERY finicky especially if using an older or newer version it can cause crashes, menus not to work, features not to work, things not to work properly.
A good example is that Icould NOT get automask to work, there would be no box to control it until I did this full reset.
One caution is that your backup project files will be erased when doing this:
How to Reset kdenlive entirely
rm ~/.config/kdenlive-layoutsrc
rm........
The below appears at first to be a bad mirror DNS error, but if you've ruled that out you just need to clear your broken yum cache and things will be good.
yum update
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: centos.01link.hk
* extras: centos.01link.hk
* updates: centos.01link.hk
http://mirror.worria.com/centos/7.8.2003/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not........
http://vault.centos.org/5.9/os/i386/repodata/filelists.xml.gz: [Errno -1] Metadata file does not match checksum
yum clean all
yum makecache
yum update........
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........
This is sure simple if you follow the guide but it took a lot of hacking around to make this work on Debian/Ubuntu!
Now before you ask why bother running wine and python, the reason is because Python executables are NOT cross-platform. If you run pyinstaller in Linux, that binary will only run on Linux and the same if you do it in Windows. So it is preferable if you have a single environment that you can create Linux and Windows binaries from rather than running 2 separate........
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 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........
I don't consider a lot of these "extra" kernel modules "nice to have" as they often contain drivers for essential items like your soundcard, your NIC and many other devices that may not work. Sometimes you may find that "sound" or "ethernet" worked before a kernel/OS upgrade and now in the new version they don't. Often it will be because you need to install the "extra" kernel modules.
One other weird thing is that sometimes........
By default bind will not respond to outside queries for security reasons.
In most distributions you will find the default in /etc/named.conf looks like this at the top under options:
listen-on port 53 { 127.0.0.1; };
listen-on-v6 port 53 { ::1; };
directory "/var/named";........
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
........
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:........
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........
growisofs -Z /dev/sr0 critical.tar.gz.gpg
Executing 'genisoimage critical.tar.gz.gpg | builtin_dd of=/dev/sr0 obs=32k seek=0'
I: -input-charset not specified, using utf-8 (detected in locale settings)
File critical.tar.gz.gpg is larger than 4GiB-1.
-allow-limited-size was not specified. There is no way do represent this file size. Aborting.
:-( write failed: Input/output error
#remember to us........
Do you hate it when your ISPhas old cached records because of a high TTLon the DNS record of the relevant domain? In plain English this means you often can't connect to a site or service because your ISP's DNS servers haven't gotten word of the new IP address (probably because they haven't checked). There are also some that are notorious for ignoring TTL and not updating records for days!
But if you are lucky and smart enough to have your own Linux based DNS se........
initiator = client
target = server
These are the first concepts you should understand which is that in iscsi essentially the "initiator" is the client and the "target" is the server.
iSCSI is derived from the old fashioned SCSI that us oldtimers grew to love. The "i" stands for Internet and the SCSI stands for "Small Computers Systems Interface" (SCSI).
iSCSI Target (Server)Setup
targetcli is the pac........
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........
4.374647] usb_common: exports duplicate symbol usb_get_dr_mode (owned by kernel)
[ 4.403334] usbcore: exports duplicate symbol __usb_get_extra_descriptor (owned by kernel)
[ 4.427736] xhci_hcd 0000:00:15.0: xHCI Host Controller
[ 4.427844] xhci_hcd 0000:00:15.0: new USB bus registered, assigned bus number 1
[ 4.429040] xhci_hcd 0000:00:15.0: hcc params 0x200077c1 hci version 0x100 quirks 0x01109810
[ 4.429141] xhci_hcd 0000:00:15.0: cache line size of 64 is not sup........
sudo apt-get install hwloc-nox
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
hwloc-nox
0 upgraded, 1 newly installed, 0 to remove and 530 not upgraded.
Need to get 151 kB of archives.
After this operation, 453 kB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubunt........
After starting the install it stalls here:
admin/index.php?cache=0&agreelicense=1&confirmrelease=1&lang=en
If you manually refresh you get a Plugins check screen:
Installation
System
Moodle second step fails just blank screen:
https://domain.la/user/editadvanced.php?id=2
Solution: give up and choose something else it shouldn't be thi........
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........
top - 13:02:52 up 603 days, 19:19, 2 users, load average: 5.01, 4.15, 3.44
Tasks: 604 total, 5 running, 599 sleeping, 0 stopped, 0 zombie
Cpu(s): 17.7%us, 36.1%sy, 0.0%ni, 42.0%id, 4.1%wa, 0.0%hi, 0.2%si, 0.0%st
Mem: 16278908k total, 4269684k used, 12009224k free, 119672k buffers
Swap: 8k total, ........
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........
PHP Warning: Cannot load module 'XCache' because conflicting module 'apc' is already loaded in Unknown on line 0
Solution:
yum remove php-pecl-apc-*........
Getting this error on Centos 6 with PHP 5.3 when just running "php -v"
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/module.so' - /usr/lib64/php/modules/module.so: cannot open shared object file: No such file or directory in Unknown on line 0
PHP Warning: Cannot load module 'XCache' because conflicting module 'apc' is already loaded in Unknown on line 0
Solution:........
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........
Centos 5 is not supported running yum will produce an error like this:
YumRepo Error: All mirror URLs are not using ftp, http[s] or file.
Eg. Invalid release/
removing mirrorlist with no valid mirrors: /var/cache/yum/base/mirrorlist.txt
Error: Cannot find a valid baseurl for repo: base
Solution - Update this file CentOS-Base.repo
# CentOS-Base.repo........
First of all check to see which version if any you have available for a downgrade:
apt-cache showpkg packagename
Downgrade/Install old package:
apt-get install package=version
Example
apt-cache showpkg caja
Package: caja
Versions:
1.10.3-1+rafaela (/var/lib/apt/lists/packages.linuxmint.com_dists_rafaela_import_binary-amd64_Packages) (/var/........
#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 ........
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........
These errors believe it or not are simply because of not being the root user or running with sudo! However if you didn't know to try as root you'd think there was a problem with your burner or disc Essentially it looks like without root you cannot send the required scsi commands to continue writing. Ithink cdrecord should have built-in tests or safeguards to see if it has the permissions to run the required commands.
I guess for more advanced users the idea is simila........
Just make sure you have php-xdebug installed and edit your php.ini:
[xdebug]
xdebug.profiler_enable = 0
xdebug.profiler_enable_trigger = 1
xdebug.profiler_output_dir = "/tmp/xdebug/"
xdebug.output_name = "cachegrind.out.%t-%s"
Also make and set permissions on /tmp/xdebug:
mkdir /tmp/xdebug
chmod 777 /tmp/xdeb........
Using Apache 2.2 and PHP5.6 PHPBB3 is very slow to respond. Actually for some reason it takes so long to even register a log entry in access_log as in several seconds or a few minutes later it shows up in Apache. All other vhosts and Apache access stops working and freezes until the request to access PHPBB3 slowly completes.
It seems to randomly be slow if you stop using it whether for posting or reading the forums. I've migrated to different machines including........
In short the two drives in the array were /dev/sdd and /dev/sde. The kernel sees they were unplugged and have gone down as you can see below.
mdadm caught the first one being unplugged /dev/sde and disabled the missing drive. However when the final drive that was part of the array is unplugged it didn't notice at all. Instead it complains about an IO error later for drives that the kernel knows do not exist anymore.
[45817.162728] ata4: exception........
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os error was
12: Timeout on http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os: (28, 'Operation too slow. Less than 1 bytes/sec transfered the last 30 seconds')
Error: Cannot find a valid baseurl for repo: base
You would think this should be fine and simple like using a proxy with most other software?
However........
# yum -y install qemu-kvm
Loaded plugins: fastestmirror
Setting up Install Process
Loading mirror speeds from cached hostfile
* base: mirror.lzu.edu.cn
* elrepo: ftp.utexas.edu
* epel: ftp.jaist.ac.jp
* extras: mirrors.aliyun.com
* openvz-kernel-rhel6: mirror.fdcservers.net
* openvz-utils: mirror.fdcservers.net
* updates: mirrors.nwsuaf.edu.cn
Resolving Dependencies........
I keep reading these drives are slower, but they are cheap and still SSDand work very fast for my needs.
As you can see the sequential read is 481-491MB/s, if I put them in MDADM RAID10 mode (normal RAID1) they should give me well over 900MB/s and with redundancy and being very cheap for what they offer.
[1232206.315622] scsi 8:0:1:0: Direct-Access ATA ADATA SU800&........
migrating from an old OpenVZ (Centos 5) to new OpenVZ (Centos 6)
Also if migrating from 32-bit HN to 64-bit your RAM will probably be much bigger than it should be!
16x bigger
eg. 32bit HN:
total used free shared buffers cached
Mem:&nb........
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........
There was only one solution here and it was the following:
edit /etc/httpd/conf/httpd.conf
Comment the lines for the Mime Magic Module:
# MIMEMagicFile /usr/share/magic.mime
# MIMEMagicFile conf/magic
*Don't forget to restart Apache and clear your browser cache twice
I was using DefaultType and ForceType a........
This can happen because port 80 is not open, or your license has expired and/or your IP is out of date and also if the license server itself from cPanel is having issues.
In most cases as long as you have a valid license the following command will solve it:
/usr/local/cpanel/cpkeyclt
Updating cPanel license...Done. Update succeeded.
Building global cache for cpanel...Done
Cannot........
Stopping httpd: [FAILED]
Starting httpd: httpd: Syntax error on line 73 of /etc/httpd/conf/httpd.conf: Cannot load /etc/httpd/modules/mod_file_cache.so into server: /etc/httpd/modules/mod_file_cache.so: cannot open shared obje........
This is a simple fix but not a simple problem and it still doesn't make sense to me.
But in a nutshell if your target proxy server works fast when accessing directly over SSL then this may be your issue.
It seems SSL does not play nicely when the target proxy destination/host has a riduculously long key (such as 8192 bits long). Now this is normally not a problem, in fact the target server could be accessed with hardly any delay directly despite such a long key.........
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........
This seems to effect many other LG phones , specifically their keyboard app and basically makes your phone unusable where you cannot use the keyboard because that message keeps popping up and the keyboard will not load.
unfortunately lg keyboard has stopped solution:
1. Go to your settings and manage apps and find the LG Keyboard app:
2. Stop it from running, delete all data and clear all cache.
After the above you will probably find that your........
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........
[Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 404 Not Found"
The above happened when for some reason all the mirrors in my cache didn't have the files (some mirrors only keep the latest version of Centos).
Itried to block them all but that didn't help because it seemed the mirrors were all hardcoded no matter what I tried.
Here is how to fix it and reset your mirror list in Centos
cd /var/cac........
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........
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........
yum -y install mathtools
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: centos.mirror.rafal.ca
* epel: mirror.steadfast.net
* extras: mirror.agmn.ca
* rpmforge: repoforge.mirror.constant.com
* updates: centosb5.centos.org
extras ........
./configure
./configure: line 91: cd: /lib/modules/2.6.32-042stab084.25/build: No such file or directory
Error: kernel version not found.
Please make sure your kernel is configured.
dr-xr-xr-x. 4 root root 4096 Feb 21 06:13 ..
lrwxrwxrwx 1 root root 45 Feb 21 06:13 build -> ../../../usr/src/kernels/2.6.32-042stab084.25
drwxr-xr-x 2 root root 4096 Feb 12 20........
This can happen when you install RPMForge or other repos with the wrong architecture and here's how you fix it (simply uninstalling won't usually fix it):
solution
yum clean all
yum -y install openvpn
Loaded plugins: fastestmirror, presto
Loading mirror speeds from cached hostfile
* base: mirror.its.sfu.ca
* extras: centos.mirror.nexicom.net
* rpmforge: mirror.cpsc.ucalgary.ca
* up........
Error: Package: php-Monolog-dynamo-1.7.0-1.el6.noarch (epel)
Requires: php-aws-sdk
Error: php-pecl-zendopcache conflicts with 1:php-eaccelerator-0.9.6.1-1.el6.x86_64
Error: php-xcache conflicts with php-pecl-apc-3.1.9-2.el6.x86_64
Error: php-pecl-zendopcache conflicts with php-pecl-apc-3.1.9-2.el6.x86_64
Error: Package: php-horde-Horde-Vfs-2.1.2-2.el6.noarch (epel)
&n........
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........
[3805108.257042] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB)
[3805108.257052] sd 0:0:0:0: [sda] Write Protect is off
[3805108.257054] sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00
[3805108.257066] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[3805108.257083] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB)
[3805108.257090] sd 0:0:0:0: [sda] Write Protect is off........
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........
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........
/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........
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........
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........
Another new drive bad from the start:
Jun 2 15:14:18 one-desktop kernel: [15895.386779] ata2.00: exception Emask 0x50 SAct 0x1 SErr 0x280900 action 0x6 frozen
Jun 2 15:14:18 one-desktop kernel: [15895.386782] ata2.00: irq_stat 0x08000000, interface fatal error
Jun 2 15:14:18 one-desktop kernel: [15895.386784] ata2: SError: { UnrecovData HostInt 10B8B BadCRC }
Jun 2 15:14:18 one-desktop kernel: [15895.386788] ata2.00: cmd 60/0........
Solution To The Following:
yum -y install zlib-devel
yum -y install e2fsprogs*
*** Cannot find /usr/include/et/com_err.h. (yum install libcom_err-devel) ***
Installation didn't pass, halting install.
Once requirements are met, run the following to continue the install:
cd /usr/local/directadmin/scripts
./install.sh
Common pre-install commands:
http://help.directadmin.com/it........
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........
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.........
I've used rsync again for this because I found it very simple, I've only excluded the Cache directory since it's not necessary and could be several GB in size.
rsync -Phaz --exclude=Cache/* user@remotehost.com:/home/user/.mozilla/firefox/profile.default/* /home/user/.mozilla/firefox/ec1n9opl.default/
This is a great way once again to get going how you were on the old/remote computer fairly quickly. It even restores all of your history in........
The best way is to use rsync, I've set it up so it doesn't copy unnecessary files, or at least ones I'm sure aren't needed.
Here is the rsync command Iused (adapt to your specific Thunderbird profile location):
rsync -hazv user@remotehost.com:/home/user/.thunderbird/sbrer.default/* /home/user/.thunderbird/4nyb0.default/ --exclude=global* --exclude=Cache --exclude=ImapMail --exclude=Mail
This is a great way to get your e-mail accounts going on a new c........
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........
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........
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
[........
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........
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........
One thing to note about DNS servers and providers is that they aren't always trustworthy, not even if they're Google or your favorite ISP. Any DNS server can compromise your privacy, and they are likely tracking your browsing habits and keeping logs of it. Sometimes it's for Marketing/Research purposes such as Google's GMail service which they admit is scraped/datamined. I would expect nothing less from their DNS service.
The other danger with such widely used and pu........
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........
mod_status is a great way to track down the source of high CPU usage and to find what vhost/script is the cause of it.
It gives you a live view of bandwith usage, CPU usage, and memory usage broken down by domain/vhost and script/URI.
Enable mod_status
vi /etc/httpd/conf/httpd.conf
ExtendedStatus On
SetHandler server-status
Order Deny,Allow
Deny from all
All........
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........
This happened during a RAID array check:
SMART says both drives pass the test, but I'm doing a long test on them and hopefully this is not a hardware error.
Apr 3 04:22:01 remote kernel: md: syncing RAID array md2
Apr 3 04:22:01 remote kernel: md: minimum _guaranteed_ reconstruction speed: 1000 KB/sec/disc.
Apr 3 04:22:01 remote kernel: md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for reconstruction.
Apr........
My mother needed a new laptop and I recommended her the same one I would have bought myself or my wife, that means the cheapest possible laptop with the most features for the money.
This HP shines at this price point and one thing that made me stay away from buying more and recommending HP/Compaq was the poor battery life. Not anymore, this model has an industry leading up to 4 hours of battery life.
Key Factors for Choosing It:
HDMI Out........
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........
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........
[137392.910057] ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x80000 action 0x6 frozen
[137392.910077] ata4: SError: { 10B8B }
[137392.910095] ata4.00: cmd 60/20:00:00:00:00/00:00:00:00:00/40 tag 0 ncq 16384 in
[137392.910099] res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
[137392.910122] ata4.00: status: { DRDY }
[137392.910135] ata4: hard resetting link
[137393.440060] ata4: SATA link........
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........
[27969.398749] sd 5:0:0:0: [sdb] 3907029168 512-byte hardware sectors (2000399 MB)
[27969.398749] sd 5:0:0:0: [sdb] Write Protect is off
[27969.398749] sd 5:0:0:0: [sdb] Mode Sense: 00 3a 00 00
[27969.398749] sd 5:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[27972.117543] ata6.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0
[27972.117543] ata6.00: irq_stat 0x48000000
[27972.117543] ata6.00: cmd 60/08:00:ff:7........
This is obviously a bug in the r8169 kernel module and it seems to affect a lot of people. I upgraded to the latest kernel and hope this won't happen anymore, as it is a very serious error. This is especially serious for those who are running servers with this chipset, who can afford for the NIC to randomly go off-line for no apparent reason?
[655548.189113] type=1505 audit(1277067560.902:5): operation="profile_load" name="/usr/bin/freshclam&q........
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........
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........
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........
This drive is clearly on the way out, the Kernel knows it but I'm surprised that SMART is not concerned. I didn't blame Seagate for their past issues until now. This hard drive has hardly been used and has not even been powered on for a year according to SMART.
Home page is http://smartmontools.sourceforge.net/
=== START OF INFORMATION SECTION ===
Model Family: Seagate Barracuda 7200.11
Device........
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........
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........
I thought I was being smart, I wanted to download some Debian packages so I went to /var/cache/apt/archives and did "rm -rf *" but then I couldn't use apt-get anymore. I kept getting this error:
E: Archive directory /var/cache/apt/archives/partial is missing.
E: The list of sources could not be read.
The solution was to recreate the "partial" directory inside /var/cache/apt/archives and then everything will be fine.........
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........
Basic Port ListingHopefully someone finds this useful or at least interesting.
http://www.sans.org/top20/#u9
Name Port Protocol Description
Small services ........
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........
Here is an example that I recently found, most PR checkers will say this domain is PR8 or will say "cannot analyze PR".
The example is domain "bonserotica.com" view Google's cache of the homepage and you'll see as in the picture below, it lists a different URL, which means they used a redirect to a high PR site to fool you and the PR checkers.........
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........
Server not using user level security and no password supplied.
tree connect failed: NT_STATUS_WRONG_PASSWORD
That happens when trying to use smbclient to connect to a share. The weird thing is that I can authnenticate just fine from Windows XP.
It is partially my mistake, I forgot this share does have a password. I've tried authenticating with the correct user and also with "Guest" because this works in Windows. In Linux I ........