• Cloned VM/Server/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........
  • 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........
  • File "/usr/local/lib/python3.5/dist-packages/pip/_internal/utils/entrypoints.py", line 12 f"pip{sys.version_info.major}", ^ SyntaxError: invalid syntax python pip3 error solution


    Is python3-pip pip3 not working anymore? Traceback (most recent call last): File "/usr/bin/pip3", line 11, in sys.exit(main()) File "/usr/local/lib/python3.5/dist-packages/pip/__init__.py", line 11, in main from pip._internal.utils.entrypoints import _wrapper File "/usr/local/lib/python3.5/dist-packages/pip/_interna........
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    Normally syntax highlighting is the default behavior. You can enable it manually by hitting :syntax on But normally you'll have this error because of the missing package. E319: Sorry, the command is not available in this version Solution install the vim-gui-common package: apt install vim-gui-common After that you should find that the code is highli........
  • 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://........
  • request_module: runaway loop modprobe binfmt-464c Kernel panic - not syncing: No init found Pid: 1, comm: swapper/0 Not tainted solution


    request_module: runaway loop modprobe binfmt-464c Kernel panic - not syncing: No init found Pid: 1, comm: swapper/0 Not tainted This is usually caused by a mismatch in architecture and happens frequently in development environments. Here is a example of what caused this issue: Your binaries are based on one architecture Your kernel was compiled with another architecture. Why does this happe........
  • kernel panic initramfs not syncing cause solution


    Check your initramfs if it's missing /dev/null or /dev/console, this is likely the reason. If you want all actual devices to be created you could also enable devtmpfs in your kernel (.config) and mount like this during init: CONFIG_DEVTMPFS=y CONFIG_DEVTMPFS_MOUNT=y mount -t devtmpfs none /dev But note devtmpfs will not create /dev/null or /dev/console for........
  • python3 error Ubuntu Linux error solution SyntaxError: invalid syntax line 12 pip{sys.version_info.major}


    This sort of thing normally happens your python3 or pip3 has been updated, because you have to in order to use pip, but the newer pip now breaks compatibility with your old python (3.5 in this case). There are a few solutions, the easiest is perhaps to upgrade to a newer OS with a newer distro provided Python 3 or to manually install a newer version of Python/OR use a PPA like deadsnakes that provides newer versions. ........
  • Centos 7 not mounting /etc/fstab partitions


    If you are doing a custom deployment and image, make sure that when you rsync'd or tar'd that you didn't mess up the symlnk of /etc/mtab to /proc/self/mounts ln --force -s /proc/self/mounts /etc/mtab Will fix this........
  • ecryptfs How To Backup / Migrate Linux Mint Ubuntu Debian system ecryptfs properly and restore access


    In this scenario, let's say you want to clone your OS at the filesystem level and the source system (the system you want to clone from) is in use. Doing a blind rsync / is a big problem because it uses twice as much space for no reason. The reason for this is that with ecryptfs you have a /home/.ecryptfs directory which has the actual encrypted versions of your files and folders. However your home directory (eg. /home/someuser) is mounted. Doing the blind rsync will ca........
  • 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........
  • 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........
  • Cisco Howto Configure Console Port/Terminal/Comm Server with Async Cable Setup


    This assumes that you've already installed the relevant HWIC cards eg. Cisco Asynchronous Serial NIM These are essentially cards that you install into your router, once installed you connect an Async cable to one of the ports on the card which normally gives you 8 console cables and are normally labelled 1 through 8. You connect all of the cables to the devices you need (even non-Cisco devices) whether switches, routers or firewalls, they will usually work. The real m........
  • How To Replace Audio Track of Video using ffmpeg


    A very common use case is that you don't want to waste time using a video editor that requires you to open it up and manually import the video clip and audio clip, then manually delete the old audio track and import the video and new audio. That's too much work and time since we don't want to go through the hassle. ffmpeg is our solution, all we have to do is specify 3 variables and we're done! -i Windows2019-Server-Noaudio.mp4 is our in........
  • mdadm how to stop a check


    Is a mdadm check on your trusty software RAID array happening at the worst time and slowing down your server or NAS? cat /proc/mdstat Personalities : [raid1] [raid10] md127 : active raid10 sdb4[0] sda4[1] 897500672 blocks super 1.2 2 near-copies [2/2] [UU] [==========>..........] check = 50.4% (452485504/897500672) finish=15500.3min speed=478K/sec ........
  • 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........
  • named bind errors - DNSKEY: unable to find a DNSKEY which verifies the DNSKEY RRset and also matches a trusted key for '.'


    Mar 22 13:46:14 box named[31767]: validating @0x7f51bc001550: . DNSKEY: unable to find a DNSKEY which verifies the DNSKEY RRset and also matches a trusted key for '.' Mar 22 13:46:14 box named[31767]: validating @0x7f51bc001550: . DNSKEY: please check the 'trusted-keys' for '.' in named.conf. Mar 22 13:46:14 box named[31767]: error (broken trust chain) resolving './NS/IN': 192.36.148.17#53 One possibility is sometimes that your time is ou........
  • httpd: Syntax error on line 221 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot load modules/libphp5.so into server: /lib64/libresolv.so.2: symbol __h_errno, version GLIBC_PRIVATE not defined in file libc.s


    httpd: Syntax error on line 221 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot load modules/libphp5.so into server: /lib64/libresolv.so.2: symbol __h_errno, version GLIBC_PRIVATE not defined in file libc.so.6 with link time reference This is usually caused by a mismatch in OpenSSLversion. Interestingly enough a lot of times if it has happened during an update of your system, or after, usually just restarting httpd........
  • Convert and install to LUKS Encrypted Drive Ubuntu 18.04 19.10 Linux Mint and Debian Based Linux


    The reason for doing this is that the installer doesn't seem to work properly for LUKS and the server installer doesn't even support LUKS anymore. When you use the GUI install on Desktop for LUKS it won't boot and will just hang after you enter your password. So the only reliable way is to do it ourselves. 1.) Make a default minimal install of Ubuntu 2.) Have a secondary disk on the server or VM. 3.)........
  • CentOS 8 how to convert to a bootable mdadm RAID software array


    The cool thing here is that we only need 1 drive to make a RAID 10 or RAID 1 array, we just tell the Linux mdadm utility that the other drive is "missing" and we can then add our original drive to the array after booting into our new RAID array. Step#1 Install tools we need yum -y install mdadm rsync Step #2 Create your partitions on the drive that will be our RAID array Here I assume it is /dev........
  • ADATA USB Thumb Drive Issues


    This is the reason that I don't like the new ADATA USB drives such as the UV128/64GB or 128GB drives and other ones that look to be the same style (the green sliding USB connector). They just don't work well from new and never work properly at any point. [ 788.242463] usb 1-1.2: new high-speed USB device number 16 using ehci-pci [ 788.339816] usb 1-1.2: New USB device found, idVendor=125f, idProduct=db8a [ 7........
  • ssh how to connect using a SOCKS 5 proxy with nc and proxycommand


    This is not about using ssh as a proxy, but rather, using a proxy when you are SSHing to another host and using ProxyCommand (where we normally use nc as our proxy tool). In newer versions of nc the syntax has changed to the following: ssh -o ProxyCommand="nc -x 127.0.0.1:1234" %h %p user@host The format must be like above in newer nc versions. Just be sure to change the 1234 to the port of your SOC........
  • Linux 3D Performance benchmarks with glxgears 59-60fps solution


    You need to disable vsync like this when running glxgears: vblank_mode=0 glxgears For Nvidia drivers do this: __GL_SYNC_TO_VBLANK=0 glxgears Notice the higher than 59-60 fps results with vblank_mode=0: ATTENTION: default value of option vblank_mode overridden by environment. 7919 frames in 5.0 seconds = 1583.704 FPS 8187 frames in 5.0 seconds = 1637.266 FPS........
  • mdadm force resync when resync=PENDING solution


    cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] md127 : active (auto-read-only) raid10 sdc1[0] sdb1[2] 1953382400 blocks super 1.2 512K chunks 2 far-copies [2/1] [U_] resync=PENDING bitmap: 15/15 pages [60KB], 65536KB chunk Solution force repai........
  • iptables how to log ALL dropped incoming packets


    A lot of people just have a -j DROP to drop all unwanted traffic or traffic not explicitly allowed but there is a better solution if you want real and proper logging: Here is another example of more advanced iptables rules. Take an example iptables rules file -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A INPUT -i eth1 -p icmp -j ACCEPT........
  • DRBD Errors Caused By Physical Corruption


    In a RAID array I had a have periodically lost a drive here and there over the past several months. Iwas always able to readd and resync without losing data. However at some point it looks like some minor corruption happened and this makes DRBD unhappy. Using fsck did not help either. Dec 19 06:01:45 storageboxtest4 kernel: [19005.945890] EXT3-fs error (device drbd0): ext3_get_inode_loc: unable to read inode block - inode=22184379........
  • 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........
  • syntax error, unexpected T_SL in PHP Solution


    This happened in a PHPscript with heredoc but it could really happen anywhere. The issue was whitespace in code like this: $variable = ........
  • 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........
  • Starting httpd: httpd: Syntax error on line 221 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot load /etc/httpd/modules/libphp5.so into server: /etc/httpd/modules/libphp5.so: cannot open shared object file:


    Starting httpd: httpd: Syntax error on line 221 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot load /etc/httpd/modules/libphp5.so into server: /etc/httpd/modules/libphp5.so: cannot open shared object file: No such file or directory This is basically caused by the PHPmodule specified in php.conf being non existent. The error tells us it couldn't fnd /etc/httpd/modules/libphp5.so........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands


    [root@localhost:~] BootModuleConfig.sh echo host-ind nfcd........
  • Python SyntaxError: Missing parentheses in call to 'print'


    SyntaxError: Missing parentheses in call to 'print' This is an annoying issue where the syntax betweenPython 2 and 3 changed which breaks old scripts. print "hello" #change to print("Hello, World!")........
  • 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


    Server Side Config 1.) First install nfs-utils yum -y install nfs-utils 2.) Configure nfs share Create a directory for your NFS share mkdir /datastore Create your NFS share in /etc/exports echo "/datastore 10.220.101.0/24(rw,sync,no_root_squash)" >> /etc/exports systemctl restart nfs........
  • Install NFS (Network File System) On Debian Linux Ubuntu Mint Howto


    sudo apt-get install nfs-kernel-server #oops there are no exports so it won't startsudo /etc/init.d/nfs-kernel-server start* Not starting NFS kernel daemon: no exports. #we will use the /tmp/nfstestshare directory for our NFS share mkdir /tmp/nfstestshare #add it to /etc/exports (basically what NFS checks to determine what to make an NFS share) /tmp/nfstestshare 192.168.1.5(rw,sync,........
  • 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........
  • mdadm how to stop or start a check


    It's fairly simple to start or stop a check but I do wish mdadm's command had this built in. Sometimes it will do a check at the worst time causing the server to crawl to a halt. Stop check on md126: echo idle > /sys/block/md126/md/sync_action Start check on md126: echo check > /sys/block/md126/md/sync_action ........
  • Syntax error on line 221 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot load /etc/httpd/modules/libphp5.so into server: /etc/httpd/modules/libphp5.so: cannot open shared object file: No such file or direct


    Stopping httpd: [ OK ] Starting httpd: httpd: Syntax error on line 221 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot load /etc/httpd/modules/libphp5.so into server: /etc/h........
  • possible SYN flooding on ctid 42131, port 80. Sending cookies. - Solution


    The Linux Kernel interpretated a very high volume of real traffic as a DDOS attack so it basically ends up blocking your web server. possible SYN flooding on ctid 42131, port 80. Sending cookies. Simple fix edit sysctl values for max_syn_backlog sysctl -w net.ipv4.tcp_max_syn_backlog=5000 To make them permanent edit /etc/sysctl.conf echo "net.ipv4.tcp_........
  • l2tp ipsec VPN Error Sep 12 18:16:25 vps pluto[7299]: ERROR: asynchronous network error report on eth0 (sport=500) for message to 192.5.6.2 port 20640, complainant 192.5.6.2: Connection refused [errno 111, origin ICMP type 3 code 3 (not authenticated


    Sep 12 18:16:25 vps pluto[7299]: ERROR: asynchronous network error report on eth0 (sport=500) for message to 192.5.6.2 port 20640, complainant 192.5.6.2: Connection refused [errno 111, origin ICMP type 3 code 3 (not authenticated)] Some say changing the "leftprotoport=17/%any" will fix this but I have not found this to be the case. Essentially it means at least one end is blocking the ipsec packets. Sometimes the %any allows an alt........
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    It is not obvious but the rsync --help rsync --help|grep port --port=PORT specify double-colon alternate port number --port does not do anything at all actually for some strange reason it still uses 22 You have to specify a manual ssh command to make it work: -e 'ssh -........
  • 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........
  • 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 -........
  • 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! If you have trouble booting after this check this CentOS mdadm RAID booting/fixing guide. One huge caveat if you are an oldschool user or sysadmin who has avoided UEFIbooting The nor........
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    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........
  • rsync run as root sudo without password


    This is a common issue, what if a issue shouldn't have root but you want to use that user to make a full backup of a system? They of course need root access. You can actually just give them passwordless sudo access to rsync in /etc/sudoers: sudo vi /etc/sudoers yourusername ALL = NOPASSWD: /usr/bin/rsync Here is how you would execute rsync: The key thing for the remote host is to........
  • 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........
  • Linux Mint Install Netboot PXE Guide Howto


    *Update so this doesn't work it must be something to do with the path of nfs or something else but the installer fails with "Installer crashed" at the end whereas with the CD/USB it works. This assumes you've already installed and configured a separate PXE/DHCP server somewhere else and your /tftpboot directory is setup. This is for Linux Mint 18.1 but generally applies to most versions although you may have tro change things like "casper"........
  • 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.........
  • ecryptfs errors


    ecryptfs-mount-private Enter your login passphrase: Inserted auth tok with sig [ee16d84] "into the user session keyring mount: No such file or directory" [ 156.118113] ecryptfs_mount: kern_path() failed [ 156.118431] Reading sb failed; rc = [-2] [ 164.233055] traps: mate-notificati[3472] trap int3 ip:7f43d7002c13 sp:7fff162c6600 error:0 [ 166.017061] ecryptfs_mount: kern_path() failed........
  • What happens when you unplug 1 or more devices from an mdadm RAID array to simulate a failure in Linux Ubuntu/Centos/Debian?


    In short the two drives in the array were /dev/sdd and /dev/sde. The kernel sees they were unplugged and have gone down as you can see below. mdadm caught the first one being unplugged /dev/sde and disabled the missing drive. However when the final drive that was part of the array is unplugged it didn't notice at all. Instead it complains about an IO error later for drives that the kernel knows do not exist anymore. [45817.162728] ata4: exception........
  • 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........
  • Centos 5 OpenSSL does not support TLS 1.2 Apache Error


    [Thu Jan 26 14:13:31 2017] [notice] caught SIGTERM, shutting down [Thu Jan 26 14:14:00 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Thu Jan 26 14:14:00 2017] [error] Server certificate is expired: 'Server-Cert' [Thu Jan 26 14:14:00 2017] [notice] SSL FIPS mode disabled [Thu Jan 26 14:14:07 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Thu Jan 26 14:14:07 2017] [error] Server certificate is expired: 'Server-Ce........
  • 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: [17925926.174581] block drbd0: drbd_sync_handshake: [17925926.174586] block drbd0: self 2AAE66AF9252D6DB:2815BF........
  • 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........
  • ADATA SU800 256GB 3D NAND Flash SSD Test & Review


    I keep reading these drives are slower, but they are cheap and still SSDand work very fast for my needs. As you can see the sequential read is 481-491MB/s, if I put them in MDADM RAID10 mode (normal RAID1) they should give me well over 900MB/s and with redundancy and being very cheap for what they offer. [1232206.315622] scsi 8:0:1:0: Direct-Access ATA ADATA SU800&........
  • DRBD Slow Performance - 99.99 % [jbd2/drbd0-8] highiowait solution


    Tired of checking iotop and seeing that your drbd partition is using 99.99% of io all the time and finding your drbd device performs slow in general? This is especially an issue in versions of DRBD in the 8.3 tree in particular one documented case is on "8.3.13" but it likely applies to other devices. The symptoms are that resyncing is fine and normal but any reasonable amount of activity is very slow and lagged and creates a high server load and con........
  • Linux How To Recover Partition Table from Kernel and Restore Centos/Debian etc..


    We've all done this at some point, you work on the wrong shell window and this was my first time making this mistake but I deleted a partition table in fdisk, recreated it and saved it with "wq" and even ran partprobe! If you haven't rebooted yet then you can still recover your partition table, otherwise you're in big trouble. Fortunately since it was a live system and in use the kernel still had to use the old table like below:........
  • Apache Log Error Message when starting


    Usage: geoiplookup [-h] [-?] [-d custom_dir] [-f custom_file] [-v] [-i] [-l] Usage: geoiplookup [-h] [-?] [-d custom_dir] [-f custom_file] [-v] [-i] [-l] grep: Address: No such file or directory grep: not: No such file or directory grep: found: No such file or directory sh: -c: line 1: syntax error near unexpected token `|' sh: -c: line 1: `|cut -d ',' -f 2' ........
  • OpenVZ Error: Failed to load 2nd level quota solution


    Syncing private Live migrating container... Syncing 2nd level quota 11000: invalid option -- F Usage: vzdqload quotaid [-c file] commands Loads user/group qouta information from stdin into quota file. -c file use given quota file Commands specify what user/group information to load: -G grace time -U disk limits........
  • 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........
  • SELinux targeted policy relabel is required


    You may get this after a long time of not rebooting but especially if you have rsync'd a / partition or deployed an image to another VPS or computer, you will often have this issue. The good thing it usually just takes a reboot. Here is more info from Centos........
  • possible SYN flooding on port 80. Sending cookies.


    Errors like this are shown on high usage servers and ports so it is common to see it on http and even imap ports: possible SYN flooding on port 80. Sending cookies. The Linux kernel will even detect flooding on OpenVZ containers: possible SYN flooding on ctid 6000, port 993. Sending cookies. In many cases this is not an issue and is more so simply a result of regular, but high usage traffic.........
  • Cannot load /etc/httpd/modules/mod_file_cache.so into server: /etc/httpd/modules/mod_file_cache.so:


    Stopping httpd: [FAILED] Starting httpd: httpd: Syntax error on line 73 of /etc/httpd/conf/httpd.conf: Cannot load /etc/httpd/modules/mod_file_cache.so into server: /etc/httpd/modules/mod_file_cache.so: cannot open shared obje........
  • 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........
  • 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........
  • rsync backup entire system properly


    rsync -Phaz --exclude=/dev/* --exclude=/sys/* --exclude=/proc/* --exclude=/mnt/md126 / /mnt/md126........
  • Samsung Printer Password Login to change settings CLP


    First of all to find your IP you can hold the "X" button for a few seconds and it will print out the DHCP IP. Another way to find the IP that I prefer is to login to your router or switch and find a hostname that says something like "SEC001599CD2948" which will be your Samsung printer (at least for the C3xx or C4xx series of Samsung printers). The login and password for Samsung Syncthru Webservice:........
  • error: Legacy syntax is unsupported: copyright error: line 10: Unknown tag: Copyright: distributable


    Usually just modify the .spec file to resolve this: vi specfile.spec Change "Copyright: GPL" to "License: GPL" and try again.........
  • 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........
  • Centos 6 server crash - " kernel:[735188.961824] Kernel panic - not syncing: Fatal exception in interrupt Write failed: Broken pipe"


    kernel:[735188.961824] Kernel panic - not syncing: Fatal exception in interrupt Write failed: Broken pipe I'm not sure what is causing this and have never seen it on any server before.........
  • CPanel Apache httpd won't start solution: Starting httpd: Syntax error on line 2 of /etc/httpd/conf/httpd.conf: Invalid command 'Alias', perhaps misspelled or defined by a module not included in the server configuration


    root@hkhosting [/]# service httpd start Starting httpd: Syntax error on line 2 of /etc/httpd/conf/httpd.conf: Invalid command 'Alias', perhaps misspelled or defined by a module not included in the server configuration ........
  • 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........
  • 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........
  • Linux Centos 6 Weird Kernel Panic


    Kernel panic - not syncing: Attempted to kill init! Pid: 1, comm: init Not tained: 3.2.51-3.el6.x86_64 #1 Call Trace: panic+0x8c/0x1a2 forget_original_parent+0x34d/0x360 exit_notify+0x12/0x140 do_exit+0x1d8/0x400 do_group_exit_+0x50/0xc0 sys_exit_group+0x12/0x20 system_call_fastpath+0x16/0x1b panic occurred, switching back to text console........
  • sudo: sorry, you must have a tty to run sudo solution


    ./rsync.sh sudo: sorry, you must have a tty to run sudo rsync: connection unexpectedly closed (0 bytes received so far) [sender] rsync error: error in rsync protocol data stream (code 12) at io.c(601) [sender=3.0.7] Solution edit /etc/sudoers #Defaults requiretty........
  • mdadm how to add additional RAID 1 drives


    This is a great way to upgrade your RAID array or move it/copy it to a new set of hard drives. Eg. you have a current RAID 1 array on older/slower drives. Just add at least 1 of the new drives to the array, update grub/install it and then boot into it. Then you have a transparent data migration that is fully synchronized. mdadm --grow /dev/md126 --raid-devices 3 md127 : active raid1 sdc1........
  • 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


    /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........
  • Android how to copy rsync binary to main system for use in shell/ssh


    Install rsync4randroid and in the shell/ssh do this: ln -s /data/data/eu.kowalczuk.rsync4android/files/rsync /system/xbin/rsync........
  • Dell FS12-NV7 2U Server Information and Guide


    I've got one of these for testing projects from work at home and got more than I bargained for with the time I've spent on it due to the storage handing/Perc 6/i cards. My particular model came with the following: 2U Rack Mount Server with Rails 2xOpteron 2373 EE (Quad Core, there is a 6-core version that can be found at times) 16GB RAM 2 x 250GB Seagate SATA 2 x Dell Perc 6/i (horrible and a nightmare to work........
  • LSI MegaRAID Adventures, Guide and HowTo


    LSi Megaraid At first it was configured as a RAID 0, then I deleted the Virtual Disk Group. I thought both drives would be shown and detected in Linux as sda and sdb but it actually shows nothing. To make them work you have to hit Ctrl+R before the system boots (when prompted) and create a Virtual Disk Group. In my case I created each one as RAID 0 (with a single drive only) as I just wanted JBOD but there is no such option or default in these Dell Pe........
  • pxe-32 tftp open timeout


    pxe-32 tftp open timeout The solution was to enable tftp in xinetd with "chkconfig tftp on". See the troubleshooting below: chkconfig --list NetworkManager 0:off 1:off 2:off 3:off 4:off 5:off 6:off acpid 0:off&n........
  • kernel: EDAC MC0: CE page 0x0, offset 0x0, grain 1073741824, syndrome 0x1a, row 2, channel 0, label "": i3200 CE


    kernel: EDAC MC0: CE page 0x0, offset 0x0, grain 1073741824, syndrome 0x1a, row 2, channel 0, label "": i3200 CE I believe this is a hardware issue, it's usually bad RAM, incompatible RAM or bad timing or even a motherboard/RAM controller.........
  • EXT4-fs error (device md20): ext4_add_entry: bad entry in directory #2552670:


    Jun 12 10:30:53 kernel: [724514.291670] EXT4-fs error (device md20): ext4_add_entry: bad entry in directory #2552670: rec_len % 4 != 0 - offset=216, inode=2553603, rec_len=94, name_len=84 Jun 12 10:30:53 kernel: [724514.292400] EXT4-fs error (device md20): ext4_add_entry: bad entry in directory #2552670: rec_len % 4 != 0 - offset=216, inode=2553603, rec_len=94, name_len=84 This happened when an unprivileged user was backing up a Windows filesystem, once they ha........
  • mdadm enable bitmap to speed up rebuilds


    Have you ever unplugged the wrong drive and then had to rebuild the entire array? It may not be a big deal in some ways but it does make your system vulnerable until the rebuild is done. Many distros often enable the "bitmap" feature and this basically keeps track of what parts need to be resynced in the case of a temporary removal of a drive from the array, this way it only needs to sync what has changed. To enable bitmap to speed up rebuilds and sync........
  • 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_........
  • 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........
  • Howto Copy/Backup/Restore All Firefox Settings/Preferences/Addons/Bookmarks to another computer/desktop


    I've used rsync again for this because I found it very simple, I've only excluded the Cache directory since it's not necessary and could be several GB in size. rsync -Phaz --exclude=Cache/* user@remotehost.com:/home/user/.mozilla/firefox/profile.default/* /home/user/.mozilla/firefox/ec1n9opl.default/ This is a great way once again to get going how you were on the old/remote computer fairly quickly. It even restores all of your history in........
  • Thunderbird How-To Copy/Backup/Restore Accounts and Settings to Another Computer


    The best way is to use rsync, I've set it up so it doesn't copy unnecessary files, or at least ones I'm sure aren't needed. Here is the rsync command Iused (adapt to your specific Thunderbird profile location): rsync -hazv user@remotehost.com:/home/user/.thunderbird/sbrer.default/* /home/user/.thunderbird/4nyb0.default/ --exclude=global* --exclude=Cache --exclude=ImapMail --exclude=Mail This is a great way to get your e-mail accounts going on a new c........
  • mdadm: /dev/sdb1 not large enough to join array solution


    mdadm --manage /dev/md1 --add /dev/sdb1 mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: /dev/sdb1 not large enough to join array md1's first primary member /dev/sda3 has 57394 cylinders while the /dev/sdb1 has 57393 (1 less cylinder) which is why it won't work. fdisk -l /dev/sda3 Disk /dev/sda3: 47........
  • Firefox 11 solution for hidden tabs to the right


    After about 15 tabs I believe, they become hidden on the right side and are accessible only by furiously clicking the "right arrow" and even then it takes forever and honestly this hidden tab feature seems to slow down everything. If you enter "about:config" in your browser without the quotes just set this value to get rid of this annoying (one of many new) feature from Firefox (set it to false and restart your browser): services.sync.prefs.sync.brows........
  • HowTo Migrate and Import iPhone/Outlook Contacts into Android without using GMail using .vcf files


    I searched for days after getting my Galaxy Note and couldn't find a way to do this (at least not without buying programs for either Android/Windows). All I read was ways to sync and import the contacts to GMail but I don't want to use GMail for privacy reasons. GMail/Google steal all of your personal information and use it for whatever purposes they want to and may sell or release it to who knows where (I don't care what their policy says but this stuff happens), just like the default........
  • Ubuntu 10.04 Flash Videos have tearing/lines Solution


    This is what I call a ridiculous bug in compiz that causes it. The solution/To fix it just install "compizconfig-settings-manager" Open it up and Navigate to General Options -> Display Settings Set the "Refresh Rate" to the current refresh rate of your monitor. For ATI cards with slow window dragging/response supposedly disabling "Sync to VBlank" fixes that but otherwise leave it as is.........
  • 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 [........
  • vi disable color syntax highlighting/can't read syntax highlighting


    Within vi if you can't exit /etc/vim/vimrc you can type :syntax off And to turn it back on: :syntax on Many of us have a dark/black background in our terminal/shell making the default syntax unreadable, the solution is to either turn off syntax highlighting with :syntax off or to enable a special option in /etc/vim/vimrc Edit /etc/vim/vimrc The "syntax on" enables the highligh........
  • Openvz migration error solution Error: Failed to suspend container CPT ERR: f68cf000,25000 :foreign process 15755/14731(vzctl) inside CT (e.g. vzctl enter or vzctl exec). CPT ERR: f68cf000,25000 :suspend is impossible now.


    Starting online migration of CT 25000 to 192.168.5.1 Preparing remote node Initializing remote quota Syncing private Live migrating container... Error: Failed to suspend container CPT ERR: f68cf000,25000 :foreign process 15755/14731(vzctl) inside CT (e.g. vzctl enter or vzctl exec). CPT ERR: f68cf000,25000 :suspend is impossible now. CPT ERR: f68cf000,25000 :foreign process 15755/14731(vzctl) inside CT (e.g. vzctl enter or........
  • 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........
  • GRUB Solution to error "Error 6: Mismatched or corrupt version of stage1/stage2"


    GNU GRUB version 0.97 (640K lower / 3072K upper memory) [ Minimal BASH-like line editing is supported. For the first word, TAB lists possible command completions. Anywhere else TAB lists the possible completions of a device/filename.] grub> root (hd1,0) Filesystem type is ext2fs, partition type 0xfd grub> setup........
  • How to recover from dead DRBD partition/hard drive in two simple commands


    This assumes that you've at least created the correct partition for your DRBD already. Notice that I am "diskless", that's because either your DRBD partition doesn't exist/has been renamed (eg. sdb becomes sda when sdb dies and you reboot) or because that drive is really actually dead/gone. *If you need to permanently change the partition/device for your resource be sure to edit /etc/drbd.conf on both hosts and reload the config. (replace r0 with........
  • mysql enable slow query logging/Query Cache Solution - find/track cause of slow mysqld/high IO/CPU usage


    If you have a webserver and find you have high IO/lagginess MySQL is one of the first things to check. It turns out MySQL was my problem and it was creating a high load on my server, especially for IO. How to Enable MySQL Slow Query Logging To Find Slow Performance/Queries vi /etc/my.cnf Add this anywhere under [mysqld] #slow queries log-slow-queries = /var/log/mysql/mysqlslowqueries.log long_query_time = 1........
  • 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........
  • diff: memory exhausted


    I don't have a solution other than to use rsync, I used diff on about 1.7TB of data which includes hundreds of thousands if not millions of small files to ensure nothing was missing or corrupt. diff didn't even get past the first large directory without spitting that error out. Keep in mind I used "diff -r" because that means recursive, otherwise it wouldn't compare all files and subdirectories and would be a false way of doing it.........
  • 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........
  • 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........
  • rsync and cp doesn't/won't include .hidden files


    I was shocked that options like preserve and archive made no difference! This is a big deal and will catch people off guard. Rsync include hidden files Solution: You need to use something like: rsync -Pha /source/dir/. /dest/dir *Notice the "." at the end of the source directory. cp -a still ignores them too, the solution is the same: cp -a /source/directory/. /destination........
  • 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.........
  • mdadm Centos 5 automatic resync


    This made me nervous but it's clearly a cronjob based on the messages log that happens every Sunday at about 4:22. I actually can't find any evidence of it in cron.d cron.daily but it is there somewhere obviously. What I don't get is why doesn't this cronjob do a datacheck like Ubuntu's cronscript does? When you unnecessarily rebuild the array you lose your redundancy during that point which makes your data extremely vulnerable. *Update I did a grep of &q........
  • ntpdate[30630]: no servers can be used, exiting


    You're not supposed to call ntpdate like that, it's part of the server and needs a bunch of different arguments. The chances are if your time is out of sync and you installed ntpd, you need to start the ntpd service.........
  • mdadm/md-check how to check array integrity without rebuilding


    This doesn't seem to be widely known (maybe it's in some documentation that none of us read though)but there's an easy way to check the integrity of any mdadm array: sudo echo check > /sys/block/md0/md/sync_action -bash: /sys/block/md0/md/sync_action: Permission denied sudo will never work, this only works as root since echo is not actually a binary/command. It is built-into bash. /sys/devices/virtu........
  • Cygwin and crontab backups via ssh/scp/rsync


    Install the "Editors" and "Net" groups that will give you rsync, ssh, ssh-keygen and cron. The trickiest thing that I keep forgetting about each time is you have to run "cron-config" which adds the cron service to Windows, and without doing that obviously no cron jobs will be run thus making automatic backups impossible. Warning about rsync/cygwin and using the -a archive switch. It's a good thing I caught this because it doesn't work ri........
  • rsync preserve attributes, permissions/ownership and times without being root non-root user


    One of the purposes of rsync is to backup whole filesystems and archive them but how can you do that properly and restore things to normal if all permissions and ownerships are not preserved from your root filesystem? It's not desirable to have everything running as root, especially not just for an rsync. The Easy rsync preserve permission solution for non-root users sudo is the answer and all you have to do is edit /etc/sudoers At the end o........
  • 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........
  • mdadm RAID 1 adventures


    I separated the 2 drives in the RAID 1 array. 1 is the old one /dev/sda and is out of date, while the separated other one /dev/sdc was in another drive and mounted and used with more data (updated). I wonder how mdadm will handle this: usb-storage: device scan complete md: md127 stopped. md: bind md: md127: raid array is not clean -- starting background reconstruction raid1: raid set md127 active with 1 out of 2 m........
  • mdadm won't boot due to fsck error


    Nov 29 20:17:58 ubuntu kernel: [ 1157.180789] md: md1 stopped. Nov 29 20:17:58 ubuntu kernel: [ 1157.180829] md0: unknown partition table filesystem not responding/reading properly with du or rsync (this needed an fsck). [ 2571.489217] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923106 [ 2571.942299] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923110 [ 2571.9568........
  • Ubuntu 10.04/GRUB2 mdadm won't boot


    Moving to RAID was a pain. What you have to do is the following from an existing install: Install mdadm Create your mdadm RAID 1 array on your spare hard drive. Start it with the missing disk. rsync the entire contents of your current / to the md partition. Here's a good way of doing it: rsync -Pha --exclude=/proc/* --exclude=/sys/* --exclude=/mnt/* /. /mnt/md2........
  • DRBD WFConnection Problem/Solution


    This has stumped me a few times because I keep forgetting that Centos 5.5 comes with a default iptables configuration that ends up blocking DRBD traffic,I tried all the normal things and couldn't understand why I couldn't make my normal DRBD config work. So if you have WFConnection problems and have tried the normal "mailing list" fixes, check your firewall status first! Both Nodes Say the Following: version: 8.3.8 (api:88/prot........
  • mdadm Linux Software RAID QuickStart Guide


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