/ - rtt - IT Resource

  • systemd management using systemctl and journalctl to check systemd logs


    systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system. The key commands or arguments you will use with systemctl are the following: Unit Commands:   list-units [PATTERN...]         List loaded units &nbs........
  • hwloc-nox set CPU affinity in Linux


    sudo apt-get install  hwloc-nox Reading package lists... Done Building dependency tree       Reading state information... Done The following NEW packages will be installed:   hwloc-nox 0 upgraded, 1 newly installed, 0 to remove and 530 not upgraded. Need to get 151 kB of archives. After this operation, 453 kB of additional disk space will be used. Get:1 http://archive.ubuntu.com/ubunt........
  • gvfs mount in /run/user cannot be accessed or displayed wrong permissions


    The folder contents could not be displayed Backend currently unmounting drwx------ 10 userhere group  260 Aug 23 19:40 .. ??????????  ? ?   ?      ?            ? sftp:host=192.168.8.80,user=adhoc ls: cannot access 'sftp:host=192.168.8.80,user=adoc': Input/output error $ ps aux|grep fuse one       253........
  • Debian Mint Ubuntu compiling xmr-stak


    sudo apt-get install libcurl4-openssl-dev git build-essential autotools-dev autoconf libcurl3 sudo apt-get install libcurl4-gnutls-dev git clone https://github.com/wolf9466/cpuminer-multi sudo apt-get install cmake  libpthread-* libmicrohttpd-dev libssl-dev libhwloc-dev git clone https://github.com/fireice-uk/xmr-stak-cpu.git make install cd bin chmod +x xmr-stak-cpu ./xmr-stak -O xmr........
  • Ethereum Client Errors


    INFO [07-19|12:11:51] Imported new block receipts              count=590  elapsed=8.440s     bytes=74117699  number=4870906 hash=6bc60b…934753 ignored=0 INFO [07-19|12:11:57] Imported new state entries               count=499  elapsed=9.963ms    processed=71076 pending=1526  retry=2&nbs........
  • Centos 7 - How To Install NFS and Mount Remotely


    1.) First install nfs-utils [root@bcitcourse ~]# yum -y install nfs-utils Loaded plugins: fastestmirror base                                                         &n........
  • Linux How To Free Wasted Memory RAM in Buffers


    We all know Linux is known for good memory management but is it really?  It seems all on its own with hardly anything running that you can come back in days or weeks and find that almost all of your RAM is used! And many will say "no don't worry it's buffers for optimization" but it doesn't seem to help because what is in buffers is not available to use for new programs running or ones that allocate more RAM as far as I can tell. The reason I know........
  • VirtualBox Nested Virtual Machine Containers with KVM Not Working no SVM or VMX module in the guest


    I can't get vmx cpu extensions to show up in Virtualbox guests despite enabling nested paging and enable vmx in virtualbox guest but this doesn't help that you check VT-X or the AMD Virtualization SVM it enables it for the guest to use BUT does not pass it through.  This means if you check cat /proc/cpuinfo in the guest you will see the CPU doesn't support virtualization.  It looks like VirtualBox still hasn't implemented this! But there is good news I&n........
  • VMWare 6.7 VCSA VSphere ESXi Management SSO Install Guide on Linux using the CLI


    #mount the VCSA DVD mount /dev/sr0 /mnt/cd #alternatively you could mount the iso directly mount -o loop vcsa.iso /your/mount/path #for this purpose we are using the CLI installer on Linux cd /mnt/cd/vcsa-cli-installer/lin64 #no it's not going to be that easy you can't just run vcsa-deploy like that you need to use a template or configured .json file ./vcsa-deploy Usage: vcsa-deploy [-h] [--version] [--supported-deploymen........
  • vino server error cannot login


    10/07/2018 03:05:14 PM [IPv4] Got connection from client10.10.25.1 10/07/2018 03:05:14 PM   other clients: 10/07/2018 03:05:14 PM Client Protocol Version 3.7 10/07/2018 03:05:14 PM Advertising security type 18 10/07/2018 03:05:14 PM Client returned security type 18 10/07/2018 03:05:14 PM TLS Handshake failed: Could not negotiate a supported cipher suite. 10/07/2018 03:05:14 PM Client10.10.25.1 gone 10/07/2018 03:05:14 PM Statistics:........
  • Cannot create gradle for conversations


    The main issue is it looks like Java is not configured to accept the invalid ssl cert that is coming from the download location. Exception in thread "main" java.lang.RuntimeException: javax.net.ssl.SSLException: java.security.ProviderException: java.security.InvalidKeyException: EC parameters error  export ANDROID_HOME=/home/user/Downloads/tools/ Conversations-master$ ./gradlew Downloading https://services.gradle.org/distributions/grad........
  • Linux Mint Black Screen after boot no graphics solution


    This is not the normal "black screen" issue and I was shocked to eventually find out why.  The normal advice of reconfiguring Xorg didn't work.  Even booting into "Recovery Mode" did not help. Here is the short end of the stick that fixed it: sudo apt-get install mdm mate-desktop-environment Yes you got it right, mdm and the mate-desktop-environment / gnome were somehow uninstalled.  This must be whe........
  • mdadm how to mount inactive array


    myguy@devbox:~$ sudo mdadm -As myguy@devbox:~$ cat /proc/mdstat |grep sdf md125 : inactive sdf3[2](S) sudo mdadm --manage /dev/md125 --run mdadm: started /dev/md125  ........
  • How to find and mount mdadm arrays automatically


    A great way if you have a bunch of drives and mdadm connected and are looking for backups/archives and don't know what is where!    for md in `cat /proc/mdstat|grep md[0-99]|awk '{print $1}'`; do mkdir /mnt/$md; mount /dev/$md /mnt/$md; done........
  • 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 PHP error.  You should disable all plugins and then enable one by one until you find the one that is causing the issue. &........
  • How to backup entire computer Linux Mint Ubuntu with tar


     sudo tar --ignore-failed-read  -czvf mycomputer-backup.tar.gz --exclude=/home/otheruser/* --exclude=/proc/* --exclude=/sys/* / Note the --exclude clauses and modify/add according to your needs........
  • tar how to ignore failed reads and not exit


    This is an important feature a failed read can genuinely occur if a temporary file has been removed or if you try backing up a sysetm file in /proc /sys (which you shouldn't really anyway). The way to fix this is the following switch: --ignore-failed-read   Example: sudo tar --ignore-failed-read  -czvf mycomputer-backup.tar.gz --exclude=/home/otheruser/* --exclude=/proc/* --e........
  • ffmpeg trouble concatenating similar but different files


    When things go wrong your video is basically unplayable or the first video plays fine and then freezes when moving on to the next.  Generally if both videos weren't produced with the exact 100% same settings you will have issues.  You can try the basic concat but it often won't work right. Solution for me: My example uses 3 videos in total so "n=3"  and a=1 to include audio. ffmpeg -threads 12  -i file1.mp4 -........
  • ffmpeg Unable to Use Hardware Encoding with Nvidia 3.40 Driver and GT210 card


    I believe from what I've read that this card's driver doesn't support the features after trying all known troubleshooting methods. ffmpeg -i uservideoRendered.mp4 -filter:v hwupload_cuda,scale_npp=w=1920:h=1080:format=nv12:interp_algo=lanczos,hwdownload -c:v hevc_nvenc -profile main -preset slow -rc vbr_hq -c:a copy uservideoRendered.mp4-test ffmpeg -i uservideoRendered.mp4 -filter:v hwupload_cuda,scale_npp=w=1920:h=1080:format=nv12:interp_algo=lanczos,hwdownload........
  • 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              ........
  • Migrate Centos 7 from Single HDD to mdadm RAID 10 array:


    Done on Centos 7.3 very important as clearly based on older guides it was a lot easier and more simpler!  Hint do not use grub2-install! One huge caveat if you are an oldschool user or sysadmin who has avoided UEFI booting The normal way will not work here if your Centos was using UEFI.  Newer systems use it by default. The easiest way to check is to do an fdisk -l if your sy........
  • 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........
  • process_usershare_file: stat of /var/lib/samba/usershares/dump failed. Permission denied - samba error solution


    [2017/06/12 21:14:04.991169,  0] ../source3/param/loadparm.c:3259(process_usershare_file)   process_usershare_file: stat of /var/lib/samba/usershares/dump failed. Permission denied Issue was the parent directory needed chmod 755........
  • Migrating from Linux Mint 17.2 mdadm RAID array to a new one (because I upgraded to larger drives).


    1.) Replicate the number of partitions in your new drives. gdisk /dev/sda gdisk /dev/sdb I created 3 partitions of the same same size. partition #1: +1G (/boot) partition #2: +60G (swap) partition #3: rest of it (/) #note if you are using GPT/gdisk you need to create separate a partition at least 1MB in size (in my case I would a 4th partition and mark it type ef02).........
  • mdadm how to recover from failed drive


    Remove the failed partition /dev/sde1  mdadm --manage /dev/md99 -r /dev/sde1 mdadm: hot removed /dev/sde1 from /dev/md99   Now add another drive back to replace it:  # mdadm --manage /dev/md99 -a /dev/sdf1 mdadm: added /dev/sdf1   A "cat /proc/mdstat" should show it resyncing if all is well.........
  • 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........
  • DRBD Split-brain solution


    Uh oh [17925926.174277] block drbd0: Handshake successful: Agreed network protocol version 96 [17925926.174325] block drbd0: conn( WFConnection -> WFReportParams ) [17925926.174342] block drbd0: Starting asender thread (from drbd0_receiver [1682]) [17925926.174432] block drbd0: data-integrity-alg: <not-used> [17925926.174581] block drbd0: drbd_sync_handshake: [17925926.174586] block drbd0: self 2AAE66AF9252D6DB:2815BF........
  • 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........
  • 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........
  • /dev/drbd0: State change failed: (-2) Need access to UpToDate data solution


    Everytime I've seen this error "/dev/drbd0: State change failed: (-2) Need access to UpToDate data" it is because DRBD has no disk: cat /proc/drbd version: 8.3.13 (api:88/proto:86-96) GIT-hash: 83ca112086600faacab2f157bc5a9324f7bd7f77 build by root@sighted, 2012-10-09 12:47:51  0: cs:Connected ro:Secondary/Secondary ds:Diskless/Inconsistent A r-----     ns:0 nr:0 dw:0 dr:0 al........
  • Linux Mint 17 How to Enable File Sharing Option in File Manager


    I still cannot understand how this would not be enabled by default and I struggled to find the reason why with manually installing samba etc.. wondering why the option for sharing was not in the menu.   On Linux Mint "MATE" the package is called "caja-share" and on Cinnamon it is called "nemo-share" so edit the below command as necessary: *Also note that the "samba" package is necessary as it is not inst........
  • 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........
  • Ubuntu/Debian OpenVZ Template Problems No Networking and SSH not starting


    It all comes down to a bug essentially where you are running an older kernel that doesn't support the newer Debian templates.  The solution is to update your OpenVZ kernel. Here are some symptoms of the problem/lack of kernel support:   Ubuntu Template 12.04 requires a manual network start: service networking start sshd will not start: /usr/sbin/sshd PRNG is not seeded mknod /dev/random c 1 8........
  • Nvidia Linux Card not working due to LSI 9200/SAS2008 IRQ conflict


    At first my BIOS said the card may not work right because there is no more option ROM space. I disabled the Option ROM for both LSI 1068 and 2008 chipsets, Network Boot ROM and most other PCI slots, Serial Port, etc... and the message went away but the card still does not work properly. But it still cannot initialize the card properly (does not work): [   33.943272] NVRM: This PCI I/O region assigned to your NVIDIA device is invalid:........
  • SAS2008 LSI 9200-E Linux Upgrade Flash Firmware with sas2flash


    Download from here http://www.avagotech.com/products/server-storage/host-bus-adapters/sas-9200-8e#downloads   sudo Installer_P20_for_Linux/sas2flash_linux_i686_x86-64_rel/sas2flash -listall LSI Corporation SAS2 Flash Utility Version 20.00.00.00 (2014.09.18) Copyright (c) 2008-2014 LSI Corporation. All rights reserved   &nbs........
  • Centos 6 how to guide convert LVM non-RAID into mdadm 1/10 RAID array live without reinstalling


    Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason.  Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to?  In some cases on a remote system you can't easily reinstall without physical or KVM access. So in this case you add a second physical or disk or already ha........
  • How To Install Linux Mint 17.2 on mdadm RAID with a separate boot partition


    I was surprised to see that Linux Mint at the latest 17.2 version still has NO mdadm installer option, and worse the installer will not be able to create a proper booting environment even when you do install it. How to setup mdadm in Linux mint LiveCD sudo su apt-get install mdadm # partition as you need and then create your mdadm devices # create your SWAP md0 mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sda1 /d........
  • Installing zoneminder on Ubuntu/Debian Linux Howto


    sudo apt-get install zoneminder [sudo] password for one: Reading package lists... Done Building dependency tree       Reading state information... Done The following packages were automatically installed and are no longer required:   libuser-perl python-evince kdebase-apps kwrite unixodbc   libgnomeprint2.2-data python-soappy vgabios python-metacity hddtemp   python-mediaprof........
  • rsync backup entire system properly


    rsync -Phaz --exclude=/dev/* --exclude=/sys/* --exclude=/proc/* --exclude=/mnt/md126 / /mnt/md126........
  • ECC Errors in action


    Message from syslogd@server at Sep 14 11:35:59 ...  kernel:[Hardware Error]: MC4 Error (node 1): DRAM ECC error detected on the NB. Message from syslogd@server at Sep 14 11:35:59 ...  kernel:[Hardware Error]: Error Status: Corrected error, no action required. Message from syslogd@server at Sep 14 11:35:59 ...  kernel:[Hardware Error]: CPU:6 (10:8:0) MC4_STATUS[Over|CE|MiscV|-|AddrV|CECC]: 0xdc00400021080813........
  • Weird Ubuntu Issues with NVIDIA driver/Compiz


    1.) My screensaver would take a long time to disable after hitting a key. 2.) Usually errors like below will follow. 3.) Compiz sometimes uses 100% or high CPU 4.) My window controls will disable (eg. the minimize, maximize and close buttons). It seems like Compiz or appearance/effects disable themselves.  Re-enabling Desktop Effects under Appearance temporarily fixes it. 5.) high load in general from things like "Migration" pr........
  • HP Procurve Switch 2824 CLI Telnet Experience , Guide and Tutorial


    telnet 192.168.1.54 ------------------------------------- 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........
  • Dell CS24-NV7 lspci dmidecode info


    0000:00:00.0 RAM memory: NVIDIA Corporation MCP55 Memory Controller (rev a2) 0000:00:01.0 ISA bridge: NVIDIA Corporation MCP55 LPC Bridge (rev a3) 0000:00:01.1 SMBus: NVIDIA Corporation MCP55 SMBus (rev a3) 0000:00:02.0 USB controller: NVIDIA Corporation MCP55 USB Controller (rev a1) 0000:00:02.1 USB controller: NVIDIA Corporation MCP55 USB Controller (rev a2) 0000:00:05.0 IDE interface: NVIDIA Corporation MCP55 SATA Controller (rev a3) 0000:00:05.1 I........
  • No response from subprocess (whostmgr (whostmgr)): The subprocess exited with status 12 (ENOMEM).


    No response from subprocess (whostmgr (whostmgr)): The subprocess exited with status 12 (ENOMEM). This happened on a client's VPS which ran out of memory.........
  • NS_ERROR_FAILURE (0x80004005) The virtual machine 'XP' has terminated unexpectedly during startup with exit code 1.


    The solution is to run '/etc/init.d/vboxdrv setup' and sometimes happens when upgrading VBox and the kernel modules don't get upgraded with it.  Sometimes the above doesn't work until you reboot because sometimes other unknown processes (even the file manager possibly)  may be locking the old module from being unloaded. Failed to open a session for the virtual machine XP. The virtual machine 'XP' has terminated unexpectedly during startup with exit code 1.........
  • 2CO/2Checkout Howto Enable IPN/Notification Setup & Script Info


    https://www.2checkout.com/documentation/notifications/order-created It shows all the parameters that get passed so you can make a simple script to process it. To enable 2CO Notifications you need to do the following: Login Browse to the top right to an icon that looks like a "circle with horizontal lines inside" - Notifications. Enter the appropriate URL for your IPN/Notification processing script (........
  • 2CO/2Checkout how to create recurring payment subscription button dynamically


    It was hard to find this as I find most online payment processors don't just put the basic information in plain view. Remember to set your sid (your seller id).  The below can easily be turned into a scripted PHP template to integrate into your own custom or existing payment solution. http://help.2checkout.com/articles/How_to/How-to-Sell-Recurring-Products-with-2Checkout/........
  • mysql how to kill individual process/query


    Enter the console as root mysql -u root -p Then kill the process (where 1234 = the thread ID) kill 1234 It's also a good idea to use a tool like "mtop" to monitor which processes and queries are slow, killing them is a temporary fix while you try to isolate the actual problem.........
  • 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


    <p>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.</p> <p>GIT-hash: 83ca112086600faacab2f157bc5a9324f7bd7f77 build by root@sighted, 2012-10-09 12:47:51<br /> &nbsp;0: cs:SyncSource ro:Secondary/Primary ds:UpToDate/Inconsistent A r-----<br /> &nbsp;&nbsp;&nbsp; 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<br /> &nbsp;&nbsp;&am........
  • Howto Convert Xen Image to KVM


    #count=10000 makes an image of 10000MB make sure your image is at least the same as your existing dd if=/dev/zero of=yourimage.img bs=1M count=10000 # losetup -fv newimage.raw # fdisk -cu /dev/loop0 # kpartx -a /dev/loop0 # dd if=<xenimage> of=/dev/mapper/loop0p1 # e2fsck -f /dev/mapper/loop0p1 # resize2fs /dev/mapper/loop0p1 # a lot of guides tell you to edit /etc/fst........
  • yum Centos 386 and 64 bit conflict resolution


    This can happen when you install RPMForge or other repos with the wrong architecture and here's how you fix it (simply uninstalling won't usually fix it): solution yum clean all yum -y install openvpn Loaded plugins: fastestmirror, presto Loading mirror speeds from cached hostfile  * base: mirror.its.sfu.ca  * extras: centos.mirror.nexicom.net  * rpmforge: mirror.cpsc.ucalgary.ca  * up........
  • Setting Ulimit


    I never found a solution to do it live (nothing worked that I found) so it looks like a relogin is required. Check your maximum file limit  cat /proc/sys/fs/file-max 824460   This is different than your actual's user limit which you'll see below ulimit -n 1024 Try and set it higher but it won't work ulimit -n 65000........
  • Centos Howto Upgrade to PHP 5.3 from 5.2


    It's not as simple as "yum install" as you can see below and it doesn't stop there.  yum install php53 Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile  * rpmforge: mirror.us.leaseweb.net  * extras: centos.mirror.rafal.ca  * updates: centos.mirror.nexicom.net  * base: centos.mirror.nexicom.net  * addons: centos.mirror.nexicom.net Setting up Install Process........
  • /usr/local/cpanel/bin/apache_conf_distiller 100% cpu


    On some CPanel installs we see complaints of "/usr/local/cpanel/bin/apache_conf_distiller" causing 100% cpu usage without any solution. Killing the process causes it to spawn again, actually it seems it tends to spawn multiple processes itself. Restarting CPanel itself is a temporary but not permanent solution.........
  • What a hdd hard drive and mdadm RAID array failure looks like in Linux


    [3805108.257042] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257052] sd 0:0:0:0: [sda] Write Protect is off [3805108.257054] sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00 [3805108.257066] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [3805108.257083] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257090] sd 0:0:0:0: [sda] Write Protect is off........
  • [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 I got 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........
  • 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........
  • Linux find what processes are swapping


    Here is a handy script that will check all processes and report what is swapping #!/bin/bash for pid in `ps x|awk '{print $1}'`; do result=`cat /proc/$pid/status|grep VmSwap|awk '{print $2}'|grep -v ^"0"` if [ ! -z "$result" ]; then  programresult=`ps x|grep $pid|grep -v grep`  if [ $? == 0 ]; then      program=`echo $programresult|awk '{print $5}'|grep -v ^grep`........
  • Migrate Linux Mint OS from one drive to another


    mount -o bind /proc /sda2/proc mount -o bind /dev/ /sda2/dev mount -o bind /sys /sda2/sys chroot /sda2 mint / # mount -o bind /proc /sda2/proc mint / # mount -o bind /dev/ /sda2/dev mint / # mount -o bind /sys /sda2/sys mint / # chroot /sda2 mint / # cd ~ mint ~ # ls Desktop mint ~ # cd / mint / # ls bin   Desktop  dev-temp  home      &nb........
  • mdadm increase recovery sync/resync speed slow solution/fix


    The units in echo are kB as in kilobyte. Setting a high sync speed echo 120000 >/proc/sys/dev/raid/speed_limit_min This will increase the speed, note that sometimes a rebuild is slow due to current disk activity/iowait. If that is not the cause then you may have a hardware issue (controller, cable or a bad drive). Setting a lower sync speed echo 1200 >/proc/sys/dev/raid/speed_limit_max........
  • CPanel suhosin install failed


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