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  • 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........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands

    [root@localhost:~] BootModuleConfig.sh          echo                         host-ind                     nfcd                   ........
  • 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........
  • MySQLD Server shutdown remotely unexpectedly

    170110  5:35:23 [Note] /usr/libexec/mysqld: Normal shutdown 170110  5:35:23 [Note] Event Scheduler: Purging the queue. 0 events 170110  5:35:23  InnoDB: Starting shutdown... 170110  5:35:24  InnoDB: Shutdown completed; log sequence number 0 12765401 170110  5:35:24 [Note] /usr/libexec/mysqld: Shutdown complete 170110 05:35:24 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended........
  • KVM: unknown exit, hardware reason 0x80000021 kvm_run returned -22 solution

    If the below is happening on KVM (a very weird and scary looking error) it's probably because of Windows. This has happened countless times to me where the bootsector on Windows 7/2008 becomes corrupted easily (even by a crash or shutdown).  KVM: unknown exit, hardware reason 0x80000021 kvm_run returned -22 rax 0000000000000010 rbx 0000000000000080 rcx 0000000000000000 rdx 0000000000000080 rsi 000000000025db2a rdi 000000000007db2a rsp 0000000000000200 rbp........
  • Dell Perc 6/i Restore BIOS/Bricked Solution Guide Howto

    I bricked one of my cards by following a guide from UNRAID. Step #1 from them wipes out the BIOS, but guess what?  The step where you restore the BIOS should have been done first, which is sas2flash but no version supports or is able to find my Perc 6/i.  So now I'm a bit stuck. I tried using megarec but it's funny that it can wipe the BIOS but can't forcefully reload it: megarec -writesbr 0 mpt2sas.rom Supports 1078 control........
  • Linux/Debian shutdown/reboot without going through init force

    -bash-3.1# shutdown -rn now Connection to localhost closed by remote host. Connection to localhost closed. Sometimes I work with embedded systems/custom kernels without any of the fancy init scripts and other common Linux basics that most would expect.  This means that often the "reboot" command (which uses an init script) will never work, not only that but it will hang the server and a manual power cycle or reboo........
  • MySQL NEVER delete ib_logfile0 or ibdata1 or you'll lose data

    don't delete /var/lib/mysql/ib_logfile0 or ibdata1 or mysql won't restart I didn't realize they were internal and not part of replication like the relay files! /usr/libexec/mysqld: ready for connections. Version: '4.1.22-log'  socket: '/var/lib/mysql/mysql.sock'  port: 3306  Source distribution 110127 16:31:00 [Note] /usr/libexec/mysqld: Normal shutdown 110127 16:31:00  InnoDB: Starting shutdown...........
  • vzquota : (warning) Incorrect quota shutdown for id 2333, recalculating disk usage vzquota : (error) quota check : lstat `sess_a5078fce5f569e453ab1fb39b0fc69f8': No such file or directory vzquota on failed [1]

    first container would not come up: Starting CT 2333: service vz stop OpenVZ is locked                                           [FAILED] 2010-11-29T23:26:23-0800 vzctl : CT 2333 : Starting container ... 2010-11-29T23:37:21-08........
  • SolusVM/Xen Central Backup Warning - Takes System Off-line!

    This really gives me a bad impression of SolusVM. I tried the "Central Backup" option and it does not warn that your server gets shutdown instantly in order to do the backup! Further, there is no way to pause or cancel the backup.  Thankfully this is a test/small disk usage VPS but what if someone was running something production with a large filesize? I haven't used QuickBackup but hope that isn't the same thing. Everyone should be vary car........
  • Shutdown/Power/Halt In Debian/Ubuntu/Centos Guide Systems Doesn't Work

    Different distributions such as Debian and Centos behave differently when trying to shutdown your system. shutdown -H now on Debian does not do what you'd expect.  The system won't power down, it will halt and do everything but power down. shutdown -PH now will do the job though (actually power the system off).  This is important to test especially if you are not near the system.  If you just use -P it forcefully shuts off which is not........
  • Mysqld Solution - Can't init databases /usr/libexec/mysqld: Can't read dir of '/tmp/' (Errcode: 13) /usr/libexec/mysqld: Can't create/write to file '/tmp/ibyP1qUC' (Errcode: 13) 100215 7:02:24 InnoDB: Error: unable to create temporary file; errno

    100215 07:02:24  mysqld started /usr/libexec/mysqld: Can't read dir of '/tmp/' (Errcode: 13) /usr/libexec/mysqld: Can't create/write to file '/tmp/ibyP1qUC' (Errcode: 13) 100215  7:02:24  InnoDB: Error: unable to create temporary file; errno: 13 100215  7:02:24 [ERROR] Can't init databases 100215  7:02:24 [ERROR] Aborting 100215  7:02:24 [Note] /usr/libexec/mysqld: Shutdown complete 100215 07:02:........
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