• nvidia cannot resume from sleep Comm: nvidia-sleep.sh Tainted: Linux Ubuntu Mint Debian


    This seems to happen in many different drivers but it happened more often in newer versions such as 530 vs 525. Then nvidia-modeset goes to 100% There are many reports of this appearing since driver 4.70 and I can confirm I've seen this in various machines. https://forums.de........
  • [error] (28)No space left on device: Cannot create SSLMutex Apache Solution Linux CentOS Ubuntu Debian Mint


    Have you got this error from Apache? [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [error] (28)No space left on device: Cannot create SSLMutex At first glance it appears that you may be out of disk space but the issue is ipc or interprocess communication. This will clear out the ipcs processes so things can work, this often happens during high traffic and may be a sign of DDOS. The command below will fix it, it will list al........
  • Docker Swarm vs Kubernetes Comparison Guide


    A lot of companies are unsure which solution to choose and many may not be aware of Docker Swarm as an alternative to Kubernetes. One thing that many Sysadmins find is that Docker Swarm is simply easier, quicker to setup and maintain by far than Kubernetes.........
  • How To Upgrade Debian 8,9,10 to Debian 12 Bookworm


    Step 1.) Upgrade to Debian 11 first The process to go to Debian 12 is not as smooth as 11, when trying to upgrade from Debian 10. In fact, it doesn't work directly, so you'll first need to follow this guide to update to Debian 11, reboot and come back here if successful. Step 2.) Update sources.list Update your /etc/apt/sources.list like this: deb http://........
  • apache2 httpd apache server will not start [pid 22449:tid 139972160445760] AH00052: child pid 23248 exit signal Aborted (6) solution Mint Debian Ubuntu Redhat


    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........
  • How To Setup Python3 in Ubuntu Docker Image for AI Deep Learning


    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........
  • i915 nouveau Nvidia GPU not starting lightdm Xorg failing solution for Could not determine valid watermarks for inherited state


    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........
  • 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.........
  • Ansible Tutorial - Playbook How To Install From Scratch and Deploy LAMP + Wordpress on Remote Server


    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........
  • SSH cannot connect to old servers/devices/switches/routers/Cisco/Juniper Unable to negotiate with 192.168.20.2 port 22: no matching key exchange method found. Their offer: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hell


    A lot of older devices either support telnet or very old SSH keyx algorithms which are insecure and disabled by all newer/modern SSH clients for security reasons. However, sometimes you may be on a LAN via VPNor some other secured network or for whatever reason, absolutely, need to connect to this device and sometimes old/embedded devices may not be possible to update to a newer SSH server. If you run into this you may be using a modern/newer SSH client and get thi........
  • Juniper JunOS Command Overview and Howtos Switch, Router, Firewall Tutorial Guide


    Enable "cli" mode equivalent in JunOS cli Configure Mode configure So rather than going to the console on a Cisco switch and typing "enable" and then "conf t", the equivalent in JunOS is "cli" and "configure". How Do You Apply Changes You've Made? You can make all kinds of changes to the switch, but remember they are not........
  • Huion and Wacom Tablets How To Install in Linux Mint / Ubuntu and make the stylus work properly


    It took a lot of fiddling to make a Huion Kamvas 13 Pro work in Linux but it simple once you know what to do. Don't bother searching as it is unlkely there is a guide out there that will actually make your tablet work. It mainly comes down to the fact that the hid_uclogic kernel module is buggy or doesn't support MANYof these wacom based/Huion tablets properly. What was happening with me is that Ihad the Kamvas 13 Huion setup as a secondary screen/monitor.&nb........
  • How To Setup a Cisco CME (Cisco Manager Express) Virtual Router under Linux using dynamips and dynagen


    This tutorial will get your router up and running using emulation tools. In this case we'll be getting a Cisco C7206 (C7200 series) VXR router going which also supports SCCP VOIP services. dynamips is the emulator itself and dynagen is the front-end tool that helps us control everything. It is used by tools such as gns3 and eve-ng. Together the two tools (dynamips and dynagen) allow us to create and emulate REAL router........
  • virt-resize: error: libguestfs error: could not create appliance through libvirt.


    This is caused because the user is running as qemu for virt-resize and if qemu does not have privileges to read from the source and write to the destination, it will fail with the below. So either change the uid of qemu or change the ownership of the source and target. Solution: export LIBGUESTFS_BACKEND=direct virt-resize --expand /dev/sda2 /root/kvmtemplates/windows2019-eval-template.img /root/kvmguests/kvmkvmuser4515........
  • using Xvfb on virtual remote ssh server to have X graphical programs work


    The scenario here is that you have some sort of remote headless Linux server but would like to run some programs on them and get graphical access to them. The problem is that the remote server may be an image or VMwithout any virtual GPU and even if so, it is likely without KDE or Gnome, so there's no real way to do this, unless you follow our guide. Install xvfb apt install xvfb Reading package lists... D........
  • 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]  ........
  • KMODE EXCEPTION NOT HANDLED - QEMU/KVM Won't Boot Windows 2016 or 10 Image or Physical Machine


    This should work but the key thing is having the "-cpu host" flag. Once you add the correct -cpu host flag then it should boot just fine on KVM. qemu-system-x86_64 --enable-kvm -cpu host -smp 8 -m 8192 -drive format=raw,file=the-file.img Examples can be found here on how to boot Windows properly with KVM.........
  • Ubuntu Linux Mint Debian xorg performance and tear-free tuning for AMD Radeon Based Cards


    I find that the default settings for the radeon driver that is applied to most AMD cards is horrible. For example by default TearFree is not enabled and it causes videos to have some kind of square artifacts. Here are the settings I have found most suitable for AMD cards: You need to create file in the following path and restart Xorg or your computer to apply it: *Beware that making a mistake here will possibly make your computer........
  • Linux Console Login Screen TTY Change Message


    This is all controlled by /etc/issue You can basically enter anything in there that you like, but there are preset variables that are mentioned at the end of the page that discuss this. Some examples of /etc/issue: Centos 7: S Kernel r on an m Ubuntu 16.04: Ubuntu 16.04.6 LTS n l You can also insert any of t........
  • Linux Mint Mate Customize the Lock screen messages and hide username and real name


    This is a security hole in my opinion and should be plugged by editing the lock screen ui layout: vi /usr/share/mate-screensaver/lock-dialog-default.ui #find these objects and set the visible property to false object class="GtkLabel" id="note-tab-label" object class="GtkLabel" id="auth-username-label> object class="GtkLabel" id="auth-realname-label"........
  • Cisco Router Setup Guide and Tutorial Howto With Commands and Examples


    In most of the Cisco router IOS I find the ports like ge0/0 ge0/1 and ge0/2 or whatever your ports are down. They will not even give you a link light. So one of the first tasks should be getting the port you are working with up. In my case the first goal is often connectivity with the LAN and WAN. LAN = your local area network (eg. in the office/home ) WAN= your ISP/public internet (eg. fiber/cable/dsl/ethernet).........
  • Proxmox Breaks Storage/LVM Backing If Killing QEMU-IMG


    I tried to stop a qemu-img copy or clone and it broke everything. It was fine to "stop" it from the GUI but a process still persisted so I killed the relevant qemu-img and the kernel went crazy. It also may not have helped that I tried to lvremove a different volume (an unused disk). But either way it breaks LVM (you cannot even run lvdisplay) so a reboot is necessary. Jan 17 06:45:21 testserver kernel: [ 5680.439337] systemd-udevd D 0&nbs........
  • 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........
  • 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.........
  • zenity popup messages, windows, dialogs, error messages calendars and more howto on Gnome Linux including Ubuntu, Linux Mint, Centos and more


    zenity is a nice utility as part of the gnome window manager that allows you to script from bash and retrieve the input from the user. It could also be helpful in just notifying a user when they login with a popup window. I'll give an overview of what's available with zenity: Application Options: --calendar Display calendar dialog --entry Display tex........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands


    [root@localhost:~] BootModuleConfig.sh echo host-ind nfcd........
  • 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........
  • iptables guide and examples and howto


    iptables allow port 22 example Of course change --dport and -s to suit your needs #allow certain IP to access port 22 iptables -A INPUT -p tcp -m tcp --dport 22 -s 192.168.1.0/24 -j ACCEPT # block others iptables -A INPUT -p tcp --dport 22 -j DROP........
  • Hard Drive Serial Number Examples


    The reason for this article is because a lot of us don't physically see our hard drives they are often remote in a datacenter etc and the actual serial number we see in SMART is not enough to check for some manufacturers. A good example is our first one the Toshiba === START OF INFORMATION SECTION === Device Model: TOSHIBA DT01ACA200 Serial Number: 33FMDW4AS........
  • mail command line examples of how to send an email using Linux / Unix and the Bash Shell or Scripting


    A simple way that may work for a lot of people who just need basic output for their scripts or daemons to announce an action is this: echo "body or message" | mail -s "realtechtalk.com" user@domain.com If you want to send a text file as the body just do this instead: mail -s "realtechtalk.com" user@domain.com < /tmp/sometxtfile.txt These are some ve........
  • Apache htaccess Custom ErrorDocument not working properly for root home page 403 Error Issue and Solution


    So I have a domain "testdomain.com". Inside test domain.com's root is the following .htaccess: Options +FollowSymLinks -Indexes ErrorDocument 403 /launch/index.html Order Deny,Allow Deny From All Allow From 192.168.1.2 When you visit anything other than root things work fine. Eg. if you visit http://testdomain.com/somedirfile.html It will show the right error in /launch/........
  • ffmpeg vidstab to stabilize video


    I'm having trouble making it work on very shaky video the result seems kind of warped/blurry/fish eye like and not as good as some other examples I've seen: ffmpeg -i MVI_1285.MOV -vf vidstabdetect=shakiness=10:accuracy=15 -f null MVI_1285.trf ffmpeg -i MVI_1285.MOV -vf vidstabtransform=smoothing=30:input="transforms.trf" MVI_1285.MOV.mp4 I've played around with the shakiness, accuracy etc.. but not the smoothing part.........
  • Centos 6.6/6.9 KVM VM Kernel Panic On Boot - Kernel panic - not syncing: Attempted to kill init!


    Iam not sure why this is happening neither the hostnode or VM changed. All I did was reboot the hostnode and startup the Centos VM again, also note it happened with the original kernel on the VM and also the latest 6.9 kernel as of this writing as shown below. Host Node: Centos 6.9 Kernel:2.6.32-696.6.3.el6.x86_64 Kernel: 2.6.32-042stab123.9 Same result in any kernel above........
  • 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 ........
  • How to change reserved blocks in Linux partition


    user@box:~$ sudo tune2fs -l /dev/md99 [sudo] password for user: tune2fs 1.42.9 (4-Feb-2014) Filesystem volume name: Last mounted on: /mnt/md50 Filesystem UUID: 976a8655-2619-4587-878c-dab07f7b7652 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Fi........
  • 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........
  • Centos 7 Cudaminer Nvidia setup guide


    I am using a GTX 1060 but replace the download for the driver with the correct/current version for your particular card by visiting: http://www.nvidia.com/Download/index.aspx?lang=en-us yum install automake curl openssl-devel libcurl-devel gcc gcc-c++ yum -y install kernel-devel-`uname -r` yum -y install unzip #the........
  • cudaminer freezes Linux Mint taints kernel


    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........
  • Openshot 2.2 is very unstable always crashing in Linux Mint 18.1!


    Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Missing folder chosen by user: Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Removed missing file: MAH02949.MP4 Jun 1 15:45:57 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: ui_util:WARNING Icon theme media-playback-start not found. Will use backup........
  • Track 01: 34 of 1726 MB written (fifo 100%) [buf 99%] 3.6x.Errno: 5 (Input/output error), write_g1 scsi sendcmd: cmd timeout after 1.897 (40) s CDB: 2A 00 00 00 44 A9 00 00 1F 00 resid: 6144 cmd finished after 1.897s timeout 40s write track da


    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........
  • mdadm frozen and doesn't realize array is dead/missing failed due to unplugged drives


    This was a surprising bug but I unplugged all drives for an array md127. At first it was just 1 drive and mdadm seemed to notice this. I unplugged the second drive taking the array offline but mdadm did not realize it was offline and still showed a non-existent disk as being part of it. This created problems trying to unmount it or even to stop this array with mdadm freezing. As for how to fix it I can only think of making sure you are not in a mounted path of........
  • PYCURL ERROR 22 - The requested URL returned error: 404 Not Found Solution


    # 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........
  • fdisk wq causes hung process


    I created a new partition table on a newly plugged in device and it caused fdisk to hang (even force kill does not work). It also may be a bad drive or some other issue because fdisk -l hangs after the first 2 HDDs (totaly of 8 HDDs on this system): [1232879.903596] INFO: task fdisk:27176 blocked for more than 120 seconds. [1232879.903607] Tainted: P&nbs........
  • iptables how to forward localhost port to remote public IP


    iptables -t nat -A OUTPUT -m addrtype --src-type LOCAL --dst-type LOCAL -p tcp --dport 3306 -j DNAT --to-destination ip.ip.ip.ip iptables -t nat -A POSTROUTING -m addrtype --src-type LOCAL --dst-type UNICAST -j MASQUERADE sysctl -w net.ipv4.conf.all.route_localnet=1 Make sure you substitute "ip.ip.ip.ip" for your real public IP and also the "--dport 3306" for the port you want to forward. Finally run the sysctl command and........
  • 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........
  • astrachat connection problems in Android 5.01 Lollipop


    I wanted to use Astrachat because it seems to be the only app that has video, pic and file sharing for Jabber butI cannot even connect despite any other client working fine including Xabber and others. astrachat "Oops.. We can't connect to the account that you provide above. Please recheck your account detail". Unfortunately to make it worse there doesn't seem to be any error log or more details about the issue. The jab........
  • Linux Mint/Ubuntu/Debian Window Controls Missing Solution


    If Linux Mint 17 or other has no window buttons/controls you can do the following from terminal: marco --replace& Sometimes it can be fixed if you go to your themes/appearance and choose a new one but in the case like mine where Compiz is installed but not running/working then that fix will not work and will require the marco command above. What if you can't type in a terminal Window? If you close........
  • Debian sources.list examples


    Based on this from Debian The 'distribution' can be either the release code name / alias (wheezy, jessie, stretch, sid) or the release class (........
  • libguestfs tools howto guide for mounting partitions and managing virtual machine images


    libguestfs tools howto guide for managing virtual machine images. libguestfs-tools aka guestfs tools has a lot of tools that make this very easy for you. You can easily mount partitons from an image with some of the commands below. To mount a partition #mount the kvmuser102821.img image and the /dev/sda1 partition from it to the local directory "mount" guestmount -a kvmuser102821.img -m /dev/sda1 mount ........
  • /usr/libexec/mysqld: The table 'session' is full solution


    First of all if you're getting this error it is a result of extreme database activity. If you aren't expecting it or it doesn't make sense to you 99% of the time this is a database driven script being exploited (some common examples I see often are things like phpBB being hit by dozens, hundreds or thousands of bots making constant DB write requests). The easiest way to identify this is to restart MySQL and then run the third party tool "mtop" and you'll see all........
  • .htaccess mod_rewrite preserve access to custom query string solution


    I struggled with this for awhile because sometimes you have rewritten URLs that you want to pass a query string but most of the info and examples do not support this. Take a typical example like this: RewriteRule ^(.*)-(.*)-(.*) /?module=$3&id=$2 You need to add the QSA flag to make it work like below: RewriteRule ^(.*)-(.*)-(.*) /?module=$3&id=$2 [QSA] The QSA preserves the original query string but also appends it wit........
  • drbd 8.3 hard drive failure recovery example


    drbd 8.3 hard drive failure recovery drbdadm attach r0 DRBD module version: 8.3.10 userland version: 8.3.8 you should upgrade your drbd tools! 0: Failure: (119) No valid meta-data signature found. ==> Use 'drbdadm create-md res' to initialize meta-data area. ........
  • Argument list too long solution - rm -rf new/* -bash: /bin/rm: Argument list too long


    Have you ever tried to run a command like rm to delete several hundred thousand files? Iam not sure what the limit is but any time it is exceeded you need to use a work around like below (which will delete any number of files). Solution find . -maxdepth 1 -name "*.*" -print0 | xargs -0 rm........
  • 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........
  • Asterisk iptables block bruteforce attacks howto with fail2ban


    yum -y install fail2ban vi /etc/fail2ban/jail.conf [asterisk-tcp] enabled = true filter = asterisk action = iptables-multiport[name=asterisk-tcp, port="5060,5061", protocol=tcp] sendmail-whois[name=Asterisk, dest=you@example.com, sender=fail2ban@example.com] logpath = /var/log/asterisk/messages maxret........
  • bash heredoc howto example


    template=$(cat ........
  • CPanel suhosin install failed


    /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........
  • css custom table class howto


    table.custom { border-collapse: collapse; border-style: solid; border-width: 1px; border-color: black; font-size: 11px; } table.custom td { border-collapse: collapse; border-style: solid; border-color: black; &........
  • mdadm create RAID 1 array example


    mdadm --create /dev/md2 --level=1 --raid-devices=2 /dev/sda3 /dev/sdb3 cat /proc/mdstat Personalities : [raid1] md2 : active raid1 sdb3[1] sda3[0] 1363020736 blocks super 1.2 [2/2] [UU] [=>...................] resync = 8.3% (113597440/1363020736) finish=276.2min speed=75366K/sec ........
  • eth0 changed to eth1 or eth2 and the solution to fix it


    If you move your hard drive(s) around to other computers/servers, you'll find that your eth0 keeps getting higher, the first time it will become eth1 and then eth2 etc and even higher if your server has dual or quad NICs. The reason is that udevd basically assigns eth0 tot he first NIC it finds and remembers it, if it encounters a NIC with a differentMAC, it assigns it one higher (eg. eth1). See the example below, I have eth2 now so how doI fix it?........
  • Kernel panic - not syncing: Attempted to kill init! Pid: 1,comm: init Tained: G I------------- 2.6.32-358.el6.x86_64 #1 Call Trace: [] ? panic+0xa0/0x16f [] ? do_exit+0x862/0x870 [] ? fput+0x25/0


    Kernel panic - not syncing: Attempted to kill init! Pid: 1,comm: init Tained: G I------------- 2.6.32-358.el6.x86_64 #1 Call Trace: [] ? panic+0xa0/0x16f [] ? do_exit+0x862/0x870 [] ? fput+0x25/0x30 [] ? do_group_exit+0x58/0xd0 [] ? sys_exit_........
  • bash for loop script for a specified number of times example


    for entity in {1..20}; do echo "entity=entity" done The above will loop 20 times, you could also do {2..50} etc... for entity in {0..10..5}; do echo "entity=entity" done The above will loop 10 times but will start from 0 and increment by 5 each time.........
  • badblocks in Linux to check/verify if a hard drive/HDD is good or bad


    I like badblocks and don't know a better more reliable way of checking the drive. If there are no errors from badblocks and dmesg doesn't produce any SATA related errors, the drive should be good (for now at least). I also prefer to do read and write mode, yes it takes ages but it is really the best way of doing it. This gives me the most confidence in knowing that a drive, especially a new one is at least OK at the moment. To test in read only mode........
  • FBDIMM /PC5300F RAM chips can work properly be with mixed timing/speeds


    I've read some people/sources say "the timing must match or it won't work". This is not true at least for the Supermicro boards I've tested this on. Some examples: PC2-5300F-555-12 PC2-5300F-555-11 etc.. Notice the "12" and "11" Also the ones that have a "PC2-5300F-555-11-B0" or "PC2-5300-555-11-D0" are also fine. What happens is what one would expect, the........
  • Samsung Galaxy Note Upgrade to ICS 4.0 microSDHC card not detected/dataloss after upgrading - possible solutions


    I backed up everything in the /mnt/sd_card directory thinking that some dataloss could occur for some reason but purposely left my microSDHC unbacked up thinking that "it won't touch that since it's external" and Samsung's and other manufacturers website even say this (that it won't be affected and not to worry etc). Apparently I was wrong, my microSD was "undetected" and asked to be formatted after the upgrade (there goes 3-months worth of family photos). No........
  • How To Burn ISO Image using cdrtools/dvdrtools for Linux/Unix Ubuntu/Debian/RHEL/Centos etc..


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  • Linux/Unix Open SSH Login Without Password Key Exchange including Debian, Redhat, Fedora, Ubuntu, BSD etc..


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  • Linux How to Search for text within any file using Linux/Unix - Use GREP


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