Commands tagged System Administration (11)

  • Run a file system check on your next boot.

    The empty file /forcefsck causes the file system check fsck to be run next time you boot up, after which it will be removed. This works too: sudo >/forcefsck


    38
    sudo touch /forcefsck
    johnraff · 2009-10-29 17:04:47 15
  • List all files opened by a particular command

    List all file opened by a particular command based on it's command name. Show Sample Output


    25
    lsof -c dhcpd
    d4n3sh · 2009-04-17 07:18:38 7
  • List files opened by a PID

    Lis all files opened by a particular process id. "PID" Show Sample Output


    6
    lsof -p 15857
    d4n3sh · 2009-04-17 07:16:03 5
  • Don't spam root. Log your cronjob output to syslog

    This command will log the output of your simple cronjobs to syslog, and syslog will take it from there. Works great for monitoring scripts which only produce simple output. Advantages: * This can be used by regular users, without modifying system files like /etc/syslog.conf * Reduce cron spam to root@localhost (Please stop spaming the sysadmins) * Uses common tools like syslog (and logrotate) so that you don't need to maintain yet another krufty logfile. * Still ensures that the output is logged somewhere, for posterity. Perhaps it's stored the secure, central syslog server, for example. * Seems to work fine on Ubuntu, CentOS, FreeBSD & MacOSX Show Sample Output


    6
    */5 * * * * root /usr/local/nagios/sbin/nsca_check_disk 2>&1 |/usr/bin/logger -t nsca_check_disk
    StefanLasiewski · 2010-07-02 00:47:05 5
  • Listing package man page, services, config files and related rpm of a file, in one alias

    Many times I give the same commands in loop to find informations about a file. I use this as an alias to summarize that informations in a single command. Now with variables! :D Show Sample Output


    2
    fileinfo() { RPMQF=$(rpm -qf $1); RPMQL=$(rpm -ql $RPMQF);echo "man page:";whatis $(basename $1); echo "Services:"; echo -e "$RPMQL\n"|grep -P "\.service";echo "Config files:";rpm -qc $RPMQF;echo "Provided by:" $RPMQF; }
    nnsense · 2015-05-11 16:46:01 13
  • turn off auto hard disc boot scanning for ext3


    1
    tune2fs -c -1 -i 0 /dev/VG0/data
    christian773 · 2010-05-29 08:20:35 3
  • create random numbers within range for conjob usage

    if you need to install cron jobs in a given time range. Show Sample Output


    1
    H=$(until ([ $i -le 6 -a $i -gt 0 -o $i -le 23 -a $i -gt 21 ] ); do i=$(date +%N | cut -c8-10); done ; echo $i) ; M=$(until [ $i -le 59 ]; do i=$(date +%N | cut -c8-10); done ; echo $i) ; echo $M $H \* \* \* backup-rsync-push.sh
    christian773 · 2010-05-29 08:42:43 6
  • Which .service related this file?

    I use this as an alias to get all .service files related a single installed file/conf (if it has services, of course). For rpm based systems ;) Show Sample Output


    1
    qf2s() { rpm -ql $(rpm -qf $1)|grep -P "\.service"; }
    nnsense · 2015-05-11 16:32:16 9
  • Manage "legacy" service run control links

    Change run control links from start "S" to stop "K" (kill) for whatever run levels in curly braces for a service called "myservice". NEWFN variable is for the new filename stored in the in-line shell. Use different list of run levels (rc*.d, rc{1,3,5}.d, etc.) and/or swap S with K in the command to change function of run control links. Show Sample Output


    0
    sudo find /etc/rc{1..5}.d -name S99myservice -type l -exec sh -c 'NEWFN=`echo {} | sed 's/S99/K99/'` ; mv -v {} $NEWFN' \;
    zoomgarden · 2010-01-03 00:56:57 4
  • manually set system date/time

    date MMDDhhmmYYYY date MMDDhhmm # example 27.12.1975 08:00 date 122708001975 Show Sample Output


    -1
    date MMDDhhmmYYYY
    christian773 · 2010-05-29 08:26:13 3
  • show system installation date


    -3
    tune2fs -l $(df -P / | tail -n1 | cut -d' ' -f1 ) | grep 'Filesystem created:'
    christian773 · 2010-05-29 08:15:25 4

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Print a row of characters across the terminal
shorter than alternative

get detailed info about a lan card on HP-UX 11.31

convert video to gif by ffmpeg and imagemagick
you can use any common video format. if you don't need to change the size of gif output, just remove `-vf scale=320:-1` btw, 320:-1 means width is 320px and height would be set automatically

All IP connected to my host
find all computer connected to my host through TCP connection.

Save a file you edited in vim without the needed permissions (no echo)
Write a file you edited in Vim but that you do not have the permissions to write to (unless you use sudo.) Same as #1204 but without the echo to stdout that I find annoying.

get stdout to variable and stdout at sametime
Sometimes you want to write the script output to stdout but you need to send it to email. If you use: $ var="$( ls / )"; $ echo -e "$var"; works but, you need to wait the script terminate to bufferize then print the output var; With this way, you can use/work/print the output before the variable receive all the output content, then after it you can use the variable for anything else, like send email.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

ROT13 whole file in vim.
gg puts the cursor at the begin g? ROT13 until the next mov G the EOF

Rename files in batch

command line Google I'm Feeling Lucky
opens the Google I'm Feeling Lucky result in lynx, the command line browser

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