Computer in Linux won't boot and goes to initramfs busybox Solution

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........

How to kill a docker swarm

Assign way more replicas than you have of memory on all nodes and watch the Swarm crash which can easily reproduce in a small VMfor testing. root@Deb11Docker01:~# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAM........

Linux how to get list of all timezones on system Ubuntu

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........

Linux dhcp dhclient Mint Redhat Ubuntu Debian How To Use Local Domain DNS Server Instead of ISPs

If you are running a local DNS server like named/bind and don't want to use the ISPsupplied DNS servers that are announced via a DHCP request (using dhclient) then the solution is simple. The reason should be obvious, but normally running your own DNS server will provide a more reliable, and fast DNS response and you won't have to worry about filtering as much (unless your upstream filters or proxies outgoing DNS requests). Edit /etc/dhcp/dhclient.conf........

Docker dockerd swarm high CPU usage cause solution

If you have swarm services and dockerd is creating a high load even with the containers just being idle, the easiest solution is to upgrade to a newer docker version. For example an identical config of 3 nodes, with Redis 5 with 30 replicas produces a load of about 1.45 in Debian 10 with Docker18.09.1 If I create the same setup on Debian 11, with Docker 20.10.5+dfsg1 then the CPU usage is low. One other difference I wondered is the kernel. In my test setup........

How to Configure NVIDIA GPUs with Docker on Ubuntu: A Comprehensive Guide for AI Deep Learning CUDA Solution

Welcome to our in-depth guide on configuring NVIDIA GPUs with Docker on Ubuntu. This post is tailored for developers, data scientists, and IT professionals who are looking to leverage the power of NVIDIA's GPU acceleration within Docker containers. Whether you're working on machine lea........

How to upgrade to the latest Python version on Linux Ubuntu Debian Mint 3.11

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:........

How to install and configure haproxy on Linux Ubuntu Debian

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,........

talib/_ta_lib.c:747:10: fatal error: ta-lib/ta_defs.h: No such file or directory

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........

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}") from pip._internal.cli.main import main File "/usr/local/lib/python3.5/dist-packag

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........

CentOS 7 / 8 cannot boot with with mdadm RAID array solution

This article about migrating to a CentOS 7 /8 RAID mdadm array has a lot of info but I wanted to focus specifically on what newer versions of CentOS 7 require to boot mdadm and what changes are necessary on CentOS 7.8+ CentOS 7 / 8 mdadm RAID booting requirements This assumes you are chrooting into an existing install or using it to get a new deployment ready. However, these steps can........

symbol 'grub_calloc' not found grub boot error solution / fix

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........

How To Tell Which Repository a Package Comes From Debian Mint Ubuntu

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........

Docker Tutorial HowTo Install Docker, Use and Create Docker Container Images Clustering Swarm Mode Monitoring Service Hosting Provider

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.........

Virtualbox Vbox Issue Cannot Enable Nested Virtualization Button is Grayed/Greyed Out and Unclickable HowTo Solution

In newer of versions of Virtualbox, especially above 6.0 (eg. 6.1 like the example below), a lot of times the "Enable Nested VT-x/AMD-V". If you are having this issue, you will see the option is grayed out. It doesn't mean that your computer does not support virtualization, although it is possible it is disabled in the BIOS. You can verify........

How to install Kubernetes with microk8s and deploy apps on Debian/Mint/Ubuntu Linux

Kubernetes Easy Beginners Tutorial/Architecture Guide Kubernetes is known as container orchestration and we should start at explaining the container part of it. A Container is what runs the actual application and based on an Image, and are more comparable to something like an LXC Container, Virtuozzo/OpenVZ using the Linux Kernel Namespaces feature. Containers run these images as independent, isolated operating environments under the O........

CentOS 7 8 PXEBoot Netinstall Not Working Solution "Pane is dead "new value non-exisetnt xfs filesystem is not valid as a default fs type"

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.........

How To Password Reset, Recover, Bypass, Remove and Unlock on Windows 10,8,7,Vista,XP,NT,2000,2003,2008,2012,2016,2019 Administrative Login Programs

If you've come here, don't be embarraassed, working in IT, this is the MOST common computer problem that almost everyone will encounter. The reason why I'm doing this post is because I've seen an increase from colleagues and admins having this problem and many times it's not even your fault. A common scenario is that someone acquires a new or used computer which they weren't given the password for. Fortunately Ihave a detailed list of all the options whether free or pa........

How To Get Started on Ubuntu with gpt-2 OpenAI Text Prediction

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........

Radeon R3 GPU on Debian Crashing

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] ........

How To Install Asterisk 16 17 on Debian Ubuntu Linux

Downloading and compiling from source to get the latest version of Asterisk is really simple with this guide. apt install gcc make g++ libedit-dev uuid-dev libjansson-dev apt install libxml2-dev sqlite3 libsqlite3-dev wget http://downloads.asterisk.org/pub/telephony/asterisk/asterisk-16-current.tar.gz tar -zxvf asterisk-16-current.tar.gz cd asterisk-16.6.2/ ./configure If you get this error change y........

nfs tuning maximum amount of connections

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).........

Debian Ubuntu Mint Howto Create Bridge (br0)

Having a network bridge allows you to bridge traffic under multiple devices so they can talk natively without using any special routing, iptables/firewall or other trickery. To create your bridge you need the bridge-utils package for brctl and if you want to do things like bridge VMs that run on a tap device you will need the uml-utilities which provides "tunctl". 1.) Install the utilities to make our bridge sudo apt-get i........

Windows 7,8,10 and Server 2008, 2012, 2016, 2019 Read Only Attribute Won't Go Away

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........

Linux delete unused tap devices automatically

This will find all tap devices and try deleting all of them. Of course don't run this if there is a chance an unused tap device is necessary and would not be created by the script ro application using it. for tap in `ifconfig -a|grep tap[0-255]|awk '{print $1}'`; do tunctl -d $tap done........

Linux bash prompt why does it not show username@host and the current directory?

Perhaps you've just seen this in the bash prompt: -bash-4.1# Instead of the expected user@hostname# It is probably because you are missing .bash_profile or .bashrc in your home directory Check for yourself: ls -al ~/|grep -E ".bash_profile|.bashrc" -rw-r--r--. 1 root root&nbs........

Linux Mint 18.2 Create Config File To Start Application Upon Login

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........

sudoers file in /etc warning about comments/includes!

If you see this in /etc/sudoers it is NOT a comment but an include. #includedir /etc/sudoers.d For example in Linux mint sudoers.d contains the following files: casper mintupdate README casper for example contains the following sudoers line: mint ALL=(ALL) NOPASSWD: ALL So if you are messing ar........

Thunderbird How To Disable An Email Account

Navigate to Tools -> Account Settings -> Server Settings Uncheck the following: "Check for new messages on startup" "Check for new messages every NN minutes" "Automatically download new messages". Source: http://forums.mozillazine.org/viewtopic.php?t=635510........

PHP Issues With Decoding Strange Smart Quotes And Non-Standard ASCII Characters

When using strip_tags and html_entity_decode with PHPit often breaks and produces annoying diamonds with question marks. It is probably because of characters like these: … (looks like 3 dots but it is a single weird character). ’ (looks like a normal apostraphe but it is not) ” (looks like a normal double quote but it is not). An easy way to sort this out is to copy the above and search in an ASCII table to extend the functional........

Why SMART is not smart at all and doesn't properly predict disk errors that cause a kernel panic or crash

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........

bash scripting how to create a function

function centos7 { release=`cat /etc/redhat-release|awk '{print $4}'|grep ^[7]` if [ "$release" != "" ]; then centos7='yes' fi } centos7 echo "$centos7" We create a function called "centos7" and then call it by just typing "centos7" We then access a variable that may be set........

How Does Cisco CUCM (Cisco Unified Communication Manager) Work?

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.........

genisoimage errors with long filenames and deep directory structures

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........

Linux bash shell doesn't show username, hostname or current path fix solution

Usually this is because when you created your user you added a user but didn't create their home directory and/or for some reason your .bashrc and .bash_profile in ~ (home) is broken/missing. In your home just create the following files with the following content to solve it: .bashrc and .bash_profile. To apply it just relogin/start a new bash session # .bash_profile # Get the aliases and funct........

PHP Displaying Blank Page on Apache

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........

VMWare ESXi 6.7 SSH/PowerShell CLI Commands

[root@localhost:~] BootModuleConfig.sh echo host-ind nfcd........

./xmr-stak: error while loading shared libraries: libmicrohttpd.so.10: cannot open shared object file: No such file or directory

The solution is just to install libmicrohttpd-dev ./xmr-stak ./xmr-stak: error while loading shared libraries: libmicrohttpd.so.10: cannot open shared object file: No such file or directory libmicrohttpd libmicrohttpd10 - library embedding HTTP server functionality libmicrohttpd-dbg - library embedding HTTP server functionality (debug) libmicrohttpd-dev - library embedding HTTP server functionality (development) $ sudo apt-get i........

gmail.com address failing in Postfix

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........

Mozilla Firefox Address Bar History Not Working places.sqlite corruption solution database repair

Here is the only solution Ifound that works in Firefox: *Note you could basically just copy all of the commands in bold (the rest just shows the output) Install sqlite3 sqlite3 places.sqlite sqlite> .clone places.sqlite-fixed moz_places... done moz_historyvisits... done moz_inputhistory..........

MySQL Maximum INT Size Truncation Issue/Warning

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........

Linux last command show login by IP instead of hostname

In the "last" command in Linux by default it will show the information with the hostname (not very useful at all especially since it normally truncates long hostnames). To get last to show the IP address use this: last -i The -i makes it show the numeric IP instead of hostname.........

pcimodules and lspci not working alternative solution

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........

How to disable Google Fonts in Wordpress

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........

PHP Migration from 5.3 to 5.4+ and dealing with deprecated functions

Upgrading from PHP 5.3 to 5.4+ there are many challenges basic things like mysql_connect() do not work anymore.........

M2Crypto.SSL.Checker.WrongHost: Peer certificate subjectAltName does not match host, expected fedora-archive.ip-connect.vn.ua, got DNS:mirror.ip-connect.vn.ua

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........

linux cp and mv will not overwrite due to alias!

This through me for a loop when I would do a cp -rf or mv -f nothing would get overwritten even if piping y or yes to the command. Type alias and you'll see why: alias cp='cp -i' alias l.='ls -d .* --color=auto' alias ll='ls -l --color=auto' alias ls='ls --color=auto' alias mv='mv -i' alias rm='rm -i' The -i is a safeguard against messing things up but however does mess things up worse when you know what........

vbulletin 4.2.5 after upgrading from 3.6 white screen fatal php errors

The code may lead you to believe you have an incompatible template but if you are not trying to use an old template currently that is not the issue. I actually deleted all 3.x style templates to make sure. What the issue is, is old plugins that are not compatible but Vbulletin does not seem to account for this except that you'll see a fatal PHPerror. You should disable all plugins and then enable one by one until you find the one that is causing the issue. &........

Centos 5.9 Working Vault Repo file

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........

Disable SSH Password Authentication to Increase Security and Harden SSH Linux Unix Server Ubuntu Mint Centos Debian

Just a note before you do this you should have a sure, guaranteed way into the system such as local, KVMor preferably publickey making bruteforce SSH absolutely impossible since there is no password to bruteforce and even if someone knew the password they wouldn't be able to login except from the local console (presumably you should make sure no one unauthorized has physical access). 1. Edit /etc/ssh/sshd_config Find the section like this:........

kdenlive titles/text renders as white screen when using .sh script

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:........

Linux Mint USB Kernel Tainted and Locked Port/Dev File

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........

ffmpeg Linux Mint download, compile and install howto

#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 ........

Reading package lists... Done W: GPG error: http://ppa.launchpad.net trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY D46F45428842CE5E

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........

USB 3.0 External HDD Enclosure Seagate UAS problems - [sdd] tag#1 CDB: Write(16) 8a 00 00 00 00 01 70 04 08 68 00 00 00 08 00 00

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........

Linux Mint missing ffmpeg solution to install from Ubuntu PPA

This is very annoying that ffmpeg is missing from Linux Mint! They have ffmpeg2theora which is a totally different codec and does not work as ffmpeg does at all (it is basically totally different). However on Linux Mint 17 I was able to use a Ubuntu PPA and sucessfully install ffmpeg! https://launchpad.net/~mc3man/+archive/ubuntu/trusty-media Adding this PPA to your system........

Avocent DSR8020 KVM/IP - Network Connect Error - Solution

This error is commonly due to Java security or TLS settings but there is a second issue with forwarded ports that also causes it. 1. Java Security/TLS Settings issue: This article has the solution to change them all in Linux automatically 2. Port Forwarding Issue if your Avocent DSR is behind NAT/private IP........

PHP Parse error: syntax error, unexpected '[' in phpBB3/vendor/react/promise/src/functions.php on line 15

The solution is simple this happens if you don't meet the requirements. In my case PHP 5.4 was required but I had PHP 5.3 installed. Once I installed a newer version the install of PHPBB was successful.........

Using a proxy with yum in Centos 6

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........

ERROR 2013 (HY000): Lost connection to MySQL server during query

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........

blocked for more than 120 seconds issues with iowait and timeout on Live Linux distribution while writing to physical disk

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........

mysql_real_escape_string returns an empty string solution

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........

Debian Linux Ubuntu Mint connect to pptp from terminal bash shell

apt-get install pptp-linux echo "yourvpnusername * yourpasspass *" >> /etc/ppp/chap-secrets vi /etc/ppp/peers/provpnaccounts.com enter (ignore the lines): ============ pty "pptp server.provpnaccounts.com --nolaunchpppd" name testuser #remotename PPTP require-mppe-128 file /etc/ppp/options.pptp ==========........

Avocent 8020 KVM Java Icedtea Viewer

This command in Debian/Ubuntu/Mint will get everything need installed for most Java based KVM viewers: sudo apt install icedtea-netx The following additional packages will be installed: ca-certificates-java icedtea-netx-common openjdk-8-jre openjdk-8-jre-headless It seems every other updated version of Java or Icedtea breaks things and I will save the frustration of Java for another post.........

Centos installing grub problems suspect gpt problem

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/........

Bing/Microsoft Ads flex.atdmt.com causing problems for ad tracking and site loading

I was asked to troubleshoot why a site wasn't loaded or responding properly, it turned out they were using some old javascript tracker from Bing/Microsoft that is no longer valid or working. You have to wait forever for it to time out but it really did disrupt the functionality of a very important site: flex.atdmt.com If you have the above code in javascript on your site remove or comment it out.........

How to manually mount Linux disk image partition without using losetup

In this case we want to mount partition #2 fdisk -lu Centos-6.6-x86_64.img You must set cylinders. You can do this from the extra functions menu. Disk Centos-6.6-x86_64.img: 0 MB, 0 bytes 255 heads, 63 sectors/track, 0 cylinders, total 0 sectors Units = sectors of 1 * 512 = 512 bytes Device Boot&nbs........

Centos cannot login by console or ssh session closed immediately

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........

openvz yum problem Centos 6.5 cannot find file on mirror:

#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 ........

Centos/obfsproxy errors

I never did get it working, it is too bad as obfsproxy should really be an option and integrated into the OpenVPN client and server or something similar: yum -y install python-pip python-devel No package python-pip available. #install the EPEL repo python-pip install obfsproxy python-pip install obfsproxy -bash: python-pip: command not found pip install obfsproxy &........

HP Procurve Switch 2824 CLI Telnet Experience , Guide and Tutorial

------------------------------------- ProCurve J4903A Switch 2824 Software revision I.10.77 Copyright (C) 1991-2009 Hewlett-Packard Co. All Rights Reserved. RESTRICTED RIGHTS LEGEND Use, duplication, or disclosure by the Government is subject to restrictions........

Linux Kernel EDAC errors EDAC MC0: UE row 0, channel-a= 0 channel-b= 1 labels "-": NON-FATAL recoverable (Branch=0 DRAM-Bank=0 Buffer ID = 0 RDWR=Read RAS=0 CAS=0 NON-FATAL recoverable Err=0x800 (Non-Aliased Uncorrectable Patrol Data ECC))

I'm not sure why I'm getting these but all memory modules are the exact same and all passed memtest successfully although they are ECC. I've heard that ECC RAM can't be tested as well and the kernel seems to indicate they are non-fatl recoverable errors. I wonder if the BIOS has aggressive RAM timing or maybe the controller or motherboard is bad. [ 12.716515] EDAC MC: Ver: 2.1.0 [ 12.717771] EDAC MC0: Giving out device to........

KVM/QEMU how to boot from direct kernel vmlinuz and initrd with networking

Thsi is very handy when doing your own kernel development. -m specifies how much ram (in the example it is 768MB) -kernel specifies the path to the kernel file -net tap,ifname=tap1,script=no (the ifname=tap1 is what you need to change and setup manually). *Run "tunctl -b" to create a tap device and use the one it gives you for ifname= Enable networking to the outside like this: *Note we assume that your bridge is br0 i........

cPanel How to set SSL and Dedicated IP in cPanel

Account Functions -> Change Site's IP Address Choose the domain and then click "Change" Choose the new IP 1.) Setup SSL Certificate in cPanel Click on "SSL/TLS Manager" under the "Security" section. 2.) Under " Private Keys (KEY)" Click "Generate, view, upload, or delete your private keys." Choose "Key Size: 4096........

firefox android text size inconsistent large and small text size solution

This is very annoying and also hard for web developers who want to see how things look on Android. You may be fooled into thinking you have an unclosed bracket or incompatible code but this is the "text inflation feature" which I feel should be disabled by default. It works so inconsitently that one block of text will appear small while the other will be huge and is quite annoying. The solution is simple Settings ->Display and &q........

Samsung Galaxy Note Upgrade/Update Experience from 4.0.4 with aftermarket ROMs

It really seems that 4.4.4 is not ready or stable for the i717 yet and this makes sense since it takes a lot of work/development and testing to get the factory stock ROMs working well. In the end I used the 4.1.2 based Blackstra BlackJelly because it was fast, stable and just works and feels great. The aftermarket support is great but many devs are focussed on adding features and customization that most of us don't want or need rather than getting things smooth and stable.........

CPanel Link to all of the command line options

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........

WHMCS Sending Blank E-mails Solution

After the "latest" update one of our clients asked us to figure out the issue and it turns out it is related to the mail settings. Basically all e-mails were being sent with blank text/no body. The solution Go to "Setup ->General Settings ->Mail" and just click on "Save" and it will work again. Note that this assumes you didn't break things yourself by changing any settings. WHMCS may tell y........

drbd won't create device if previous partition is on it Command 'drbdmeta 0 v08 /dev/md160 internal create-md' terminated with exit code 40

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........

drbd won't sync 8.3.13 on OpenVZ kernel

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........

PHP Warning: imagecreatefromjpeg(): gd-jpeg, libjpeg: recoverable error: Premature end of JPEG file

I was having an issue with only certain random/jpeg files with the functions imagecreatefromjpeg imagecreatetruecolor and other related ones. This issue was annoying basically it seems like a libgd issue/bug with newer versions of PHP and it was difficult to trace-out. One very useful thing that helped me was using "php-cgi" and passing the query string as an argument eg: php-cgi images.php source=IMG.jpg (that way you get all the error messages wh........

[Hardware Error]: CPU:0 MC4_STATUS[-|CE|MiscV|-|AddrV|CECC]: 0x9c054c84011c011b [Hardware Error]: cache level: L3/GEN, tx: GEN, mem-tx: RD [Hardware Error]: Northbridge Error (node 0): L3 data cache ECC error.

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........

cPanel Find/Set Main DNS Servers for Template Howto

Go to: "Server Configuration" -> Basic cPanel & WHM Setup Scroll to: "Nameservers" (at the bottom) From there you can set the names of the nameserver and their IPs. It's very weird and confusing that nothing under IP Functions/DNS has or links to this.........

kvm centos cannot compile error

./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........

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Iread this article and still don't understand the issue. If I understand correctly the client negotiates after the first SSLconnection and then gets the correct hostname and thus correct certificate. http://wiki.apache.org/httpd/NameBasedSSLVHostsWithSNI To their credit I know I'm not using SNIbecuase Iget this message in the Apache log :) [warn] Init: You should not use name-based virtual hosts in conjunction with SSL!! B........

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/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........

Dell Perc 6/i SATA benchmarks without battery

The results are not bad, the Hitachi performs the same as it does in a SATA2 motherboard. However, the 2TB is much different, on a similar 2TB Toshiba I get about 198MB/s on a different motherboard vs the 2TB Hitachi which should produce similar results. This Dell Perc 6/i is on a PCI x8 riser card and is connected to a 12-port backplane. Adapter #0 Enclosure Device ID: 32 Slot Number: 0 Enclosure position: N/A De........

Dell Perc 6/i cannot downgrade

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........

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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........

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WD 20EARX Dead Again

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........

WD 20EARX 2TB Bad within days

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:........

Bad Hard Drive Slows Down Computer

Here's a proven example of what a bad hard drive can do, it was technically functioning OKin a RAID array but the system became extremely low and the load become high and IOWAIT was even higher and I always thought it was a bad application. The truth is that this failing 1TBHitachi has slowly gotten worse and caused huge slowdowns, (eg. 100% load on Thunderbird waiting for e-mails to load etc..). After swapping it out, tabs change instantly, emails are not lagged, and........

Linux OpenOffice Convert .doc/documents to PDF format with unoconv

Install unoconv unoconv -d document -f pdf file.doc Change "file.doc" to the name of your document. Note you could specify *.doc and it will convert all .doc's in the current directory to pdf which is very handy. unoconv uses the cli from OpenOffice to do this, OpenOffice actually doesn't have an easy way I've found of doing this despite it having the functionality. ........

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This seems to be a verified bug on KVM with no solution. I wasn't able to get through the installer with Ubuntu 12.04, it would crash while "configuring apt". I was able to install it with Ubuntu 12.10 but it crashes randomly at times. This happens with the latest Centos 6.3 kernel and KVM package, I even compiled the latest version from the KVM website and used that, but the results are still the same. Here's some links to discussion about the bugs:........

OpenOffice Writer Replacing/Reformatting Dates in Tables - Howto Disable

Tools -> Options -> OpenOffice Writer -> Table Uncheck "Number Recognition" This will permanently disable it but won't undo the damage it has already done. I spent a long-time fighting with this horrible feature which should be disabled by default.........

kvm cannot boot xen guest using lvm

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........

Disable SELinux How To Tutorial Solution

Here is a quick script that works on most Centos versions to disable the virus/SELinux from blocking basic functionality. The first echo 0 statement disables SELinux instantly but it will still be enabled on reboot. The second line disables it permanently. #!/bin/bash #disable SELinux Immediately echo 0 > /selinux/enforce #disable SELinux Permanently sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config........

Asus VE247H 23.7" Inch LCD/LED Backlit Monitor Dead/Stuck Pixel Policy Complaint

I've thought for awhile that Asus has been banking on its years old reputation for quality amongst gamers and enthusiasts and I think I'm right. My Asus VE247H Monitor with a supposed 2MS refresh rate has 1 red/stuck/dead pixel but fortunately it can only be seen on a non-true black picture or against a blue screen. I have several Asus products and find they're all of fairly poor quality. First of all their motherboards have given me the most issues of any brand, they te........

KVM QEMU and Xen how to mount disk images off-line and access data

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 ........

What's Needed To Fix Linux

I really am a Linux fan but my comments here may not show it. Although I'm quite familiar with Linux CLI to administer servers, I find Linux GUI OS's like Ubuntu at times very clunky. This is partially because there's no such thing as a "self-made" Linux from scratch where the UIwas designed by a single team. Linux is made up of several different projects that are generally completely separate and this lack of integratiion is a key issue that makes things f........

mdadm/Debian problem

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........

Linux Kernel Panic Messages - Symptoms of bad RAM module/stick

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 [........

samba/smbd connection to share problems and solutions

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........

IO/delay and high load when a SATA hard drive dies

dd if=/dev/sda of=/dev/null creates ever increasing load every second. After minutes the load has moved up to 4.79 I've tried with two different discs in my system. I wonder if it's a delay or problem with the SATA bus because one drive I have connected has recently failed. I notice when drives fail that you get some IO/blocking issue when they don't respond properly. Yes I believe it was, because here's the same disc after removing the dead........

Linux Out of Memory OOM Object Killer Solution "Out of memory: kill process 1955 (sshd) score 81 or a child"

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........

How To Test If Your Hard Drive Is Good/Signs of dying hard drive

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........

smart is not smart, it thinks a dead drive is still good

I had a dying drive that smart thought until it totally disappeared was a good drive, and actually all parameters did look fine but this system was causing my system to lockup and other bad behavior: === START OF INFORMATION SECTION === Device Model: WDC WD20EARS-00MVWB0 Serial Number: WD-WMAZ20139 Firmware Version: 50.0AB50 User Capacity: 2,000,398,934,016 bytes Device........

Hitachi 2TB HDS5C3020ALA632 drive DOA

I had one of these shipped and it was not recognized when plugged in, here's what a dead drive looks like (I assume it's teh circuit board which is dead): ata1: link is slow to respond, please be patient (ready=0) ata1: softreset failed (device not ready) ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) ata1: link online but device misclassified, retrying ata1: link is slow to respond, please be patient (ready=0) ata1: softreset f........

Linux how to use find recursively to find certain types of files/extensions

Normally if you're in a certain directory you could do: find *.txt and it will work as expected, but it won't work recursively through child directories, here's the correct way to do it: find . -type f -name *.txt The "-type f" is optional because that means only files, but we could have specified d for directory etc... The above command will work recursively as you'd expect. In that way I find "find" to be un........

Virtualbox Guest Hang/Freeze Ghost Zombie VM Machine Problem/Solution

Virtualbox hang problem A VM just froze and wouldn't close so I had to force it, but the VBox GUI thinks it's running even when I close it. I manually killed the related process by doing ps aux|grep VirtualBox and found the PID 6191 I killed it with "kill -kill 6191" but it remains open and as "defunct" so I can't restart it because the GUI freezes when I click on it because it thinks it is running still........

Are my WDEARS20 Drives dying already?

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........

Dying Samsung DVDRW Drive

My Samsung drive failed on me, at first I thought it was the enclosure but a direct SATA connection causes the same problems for discs that are inserted. It will work fine for a few minutes but then starts spewing the errors below. I've never been a fan of Korean made optical drives and have always had trouble with them. The problem is that I don't believe NEC and Lite-ON make drives anymore, and I considered them the leaders. Apr 7 11:58:48 bo........

Yahoo Mail (email) DNS Server Out Of Date Problems

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........

Linux High IOWAIT updatedb can't be killed and crash with mdadm

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........

SPAMASSASSIN Enable Pyzor and DCC

*Remember to restart spamassassin after all of this. DCC wget http://www.dcc-servers.net/dcc/source/dcc.tar.Z tar -zxvf dcc.tar.Z cd dcc-1.3.138/ ./configure;make;make install #enable DCC, uncomment the line that disables it near the top vi /etc/mail/spamassassin/v310.pre pyzor wget http://sourceforge.net/projects/pyzor/files/pyzor/0.5.0/pyzor-0.5.0.tar.gz/down........

SPAMASSASSIN Disable OpenWhois RBL (it is dead/defunct/no longer active):

SPAMASSASSIN Disable OpenWhois RBL (it is dead/defunct/no longer active): You might see this in your headers 2.4 DNS_FROM_OPENWHOIS RBL: Envelope sender listed in bl.open-whois.org comment out this inside /usr/share/spamassassin/72_active.cf ##{ DNS_FROM_OPENWHOIS ifplugin Mail::SpamAssassin::Plugin::DNSEval header DNS_FROM_OPENWHOIS eva........

Postfix Enable SSL/TLS with your certificate

Create Cert & Key: openssl req -new -x509 -nodes -days 1530 -out server.crt -keyout server.key mkdir /etc/mailssl chmod 700 /etc/mailssl cp server.* /etc/mailssl Postfix SSL config Edit /etc/postfix/main.cf: #SSL stuff smtpd_tls_cert_file = /etc/mailssl/server.crt smtpd_tls_key_file = /etc/mailssl/server.key To make smtps w........

CPU #1 not responding - cannot use it.

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 from sendmail when using with postfix or other MTA's

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........

named/bind cannot find zone file, load zone files without specifying full directory path/loading master file genuine.com.zone: file not found

genuine.com/IN: loading master file genuine.com.zone: file not found _default/genuine.com/IN: file not found I always found it silly that no one really talks about this and apparently many like me and even control panels like Plesk were still using hard paths. I always thought "why can't I just specify the name of the zone file and have bind find it". Surely the default search path must be /var/named or somewhere else but there is no such thing.........

updatedb/mdadm caused a kernel panic?

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........

Ubuntu 9.04 Crash

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........

Installing Webmin & Enabling SSL

Webmin Setup Centos 5: wget http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html&ts=1294339690&use_mirror=surfnet [1] 24229 [2] 24230 [root@host ~]# --2011-01-06 21:48:20-- http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html Resolving downloads.sourceforge.net... 216.34.181.........

md: data-check of RAID array md3

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'........

Ubuntu/Debian DRBD 8.0 Setup Guide

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........

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Let the numbers speak for themselves, from what I read the Load_Cycle_Count which is very high (more than 500,000/half a million times) is the number of head parks. What a stupid"Green" design and design flaw which will probably mean an early life for the drive. This is almost as silly as Seagate's new reputation for BSY/poor quality disks since the 7200.11 series. To make it worse this is also when Western Digital introduced "Advanced Format" o........

How not to change an IP address in CPanel during a migration

/usr/local/cpanel/bin/swapip domain(s) It simply doesn't work, the Apache VHOSTS remain 100% unchanged, why does this script exist? I'm sure it would work from the control panel but I am locked out because my IP was changed and it doesn't match the CPanel license. I wish CPanel would make it easier to update the license IP. I even took it a step farther, I manually edited the vhosts and restarted Apache and it........

mencoder Linux CLI video editing how to encode video file into xvid and split by time into multiple parts

Mencoder is great, you can throw anything at it, including video files from your camera and have it encode into xvid or almost any other format. In my case I took 640x480 video from my Canon and reduced the size by 1/3 with the options below (there are many other options that you can read about in the manual but I like to keep it simple). Mencoder Encode mencoder -ovc xvid -oac mp3lame -xvidencopts fixed_quant=4 -o ........

mdadm when a RAID 1 member dies

[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........

RAID 5 doomed in 2009?

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FUSE/Curlftpfs mount ftp account as drive partition in Linux

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........

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I've recently used CPanel on the admin side for the first time and have to say I hate it. Everything from the layout to the functionality screams "hackish". It just lacks so many common sense features and way of working. I was never 100% impressed with Plesk but the basics were definitely laid out and done in a sensible manner, even though it is made by a Russian company, they definitely thought about how to make a Control Panel. I have no idea why people........

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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.........

Warning: get_browser(): browscap ini directive not set. PHP Error Solution Fix

Warning: get_browser(): browscap ini directive not set. Solution is to edit /etc/php.ini Uncomment this: [browscap] browscap = extra/browscap.ini........

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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........

rsync halted froze Out of memory: kill process 7559 (rsync) score 635 or a child Killed process 7559 (rsync)

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........

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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........

MySQL TEXT field size length limit reminder, don't truncate your data!

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........

Seagate 7200.11 firmware defect in 500GB, 1000GB (1TB) and 1500GB (1.5TB) Hard Drives

Seagate Inventory/Firmware Check I heard about this issue a long time ago but never looked into it. I figured I wasn't affected since my 500GB drives were running for so long. I've been using Seagate's since 2002 and to this day all of the drives I have are alive from Seagate. *Update the bad news is that I realize one of my 500GB's is about to die, it's not even a year old, but is also not affected by the recall according to Seagate! Seagate Inventory/Firm........

Compaq V2405CA Laptop - Unixbench Performance Test

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/openssl

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........

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Javascript window.onLoadThis can be used anywhere on an HTML page, my favorite (since body onLoad is not an option for me) is to use: window.onLoad = functioncall(); Eg. to calculate the value of a form, you want to use the onLoad at the end of the form, as things are called in order of course........

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Intel's Finnish Fetish

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........

Other Security Web Sites

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........

Adventures in pre-paid SIM Cards and data GPRS/Edge/3G in China with China Mobile in Shenzhen, Guangzhou, Shanghai, Beijing and other cities

This really is a difficult and confusing process for non-Mandarin speakers, but here's what I've done and learned so far: You can purchase an "M-Zone" China Mobile pre-paid SIMCard from almost anywhere but I tried to purchase mine from Suning (a large electronics dealer) hoping they would be able to help me or answer my questions but my plan didn't work out at all. At Suning once I found someone who spoke some English they gave me the 55 RMB M-Zone China Mobile P........

iPhone Complaint Lock/Standby Disrupts WiFi and uses 3G instead

Has Apple tried to give a golden egg to the cell phone companies? Has anyone noticed that if you set your lock time to x minutes, the phone doesn't just lock, it goes into standby. When it does this, any WiFi connection you have gets dropped and all push/data functions such as e-mail checking are done through the 3G network. There is no way to change this feature and functionality and it's very annoying, especially if you are downloading something or loading files over the........

Why Apple should thank the jailbreakers and not patch/stop the jailbreaking exploits

First of all, the iPhone is crippled in many ways, but most of my complaints about functionality have been addressed through the jailbreak, Ican run apps in the background of my choosing, I can install a terminal, acccess my phone through SSH and SCP and so much more. It even addresses the 15 minute e-mail problem, I installed a program called "PushMod" and now set the checking time to just 1 minute. Apple should really thank the developers for this gift, it ma........

iPhone 3GS 32GB "Harsh Review"

Yes, Iadmit I finally got bitten by the hype as much as I can usually see through it all. Keep in mind this review is of the "stock" phone, no jailbreaking yet which is what really unleashes the customizability and whyI bought iPhone. I had better things to say about this phone before buying it, and it is a great phone, perhaps the best on the market by far, if not because of the Mac OS port onto the iPhone and all the apps, etc, etc. With that said........

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Iused to get all kinds of weird annoying characters like "�" during compilation with gcc especially. example: dmg2img.c:456: error: �BZ_OK� undeclared (first use in this function) dmg2img.c:471: warning: implicit declaration of function �BZ2_bzCompressEnd� dmg2img.c:482: warning: implicit declaration of function �BZ2_bzDecompress� dmg2img.c:484: error: �BZ_PARAM_ERROR� undecl........

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As much of a computer nerd as Iam, I'm usually a late adopter to technology for a few reasons. Ifeel most new hyped technologies and electronics are mainly fads, and I'm also cheap. Adopting later means you avoid the bugs, kinks and most importantly pay the lowest price, that's me being cheap again :) I never read much about the iPhone but Isaw all the hype around it and until recently I wasn't a big fan of anything Apple until a few years ago I realize........

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Icouldn't understand why on one system it took a few minutes to get the SSHlogin prompt when connecting to other systems. The other systems all had the UseDNS parameter set to no, which almost always resolves the login prompt delay. The reason is Ubuntu and perhaps Debian and other distributions /etc/nsswitch.conf file Edit yours to have the "hosts" line like so (notice that files and dns are the primary resolution choice........

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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........

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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 ........

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There's a lot of outdated information and confusion for system administrator's out there. One annoying task for many an Administrator has been backing up data in Linux. You don't need any GUI tools such as K3B or GnomeBaker. Both are excellent tools but for veteran command line users working remotely, using the keyboard is a great and possibly automated way to save yourself pain and hassle. At a later date we'll cover how scripting can automatically backup certain........

Comments About Networking Technology

We've noticed in many ways that traditional networking even in WANs and LANs has changed very little. Years ago most networks were running on 100mbit and today most still are. Even the average internet connection is largely unchanged from several years ago with some minor exceptions from Europe and Asia.........