Commands by px (3)

  • easily strace all your apache processes

    This one-liner will use strace to attach to all of the currently running apache processes output and piped from the initial "ps auxw" command into some awk. Show Sample Output


    7
    ps auxw | grep sbin/apache | awk '{print"-p " $2}' | xargs strace
    px · 2011-03-14 21:45:22 34
  • Easy to extend one-liner for cron scripts that automate filesystem checking

    This one-liner is for cron jobs that need to provide some basic information about a filesystem and the time it takes to complete the operation. You can swap out the di command for df or du if that's your thing. The |& redirections the stderr and stdout to the mail command. How to configure the variables. TOFSCK=/path/to/mount FSCKDEV=/dev/path/device or FSCKDEV=`grep $TOFSCK /proc/mounts | cut -f1 -d" "` MAILSUB="weekly file system check $TOFSCK " Show Sample Output


    1
    ( di $TOFSCK -h ; /bin/umount $TOFSCK ; time /sbin/e2fsck -y -f -v $FSCKDEV ; /bin/mount $TOFSCK ) |& /bin/mail $MAILTO -s "$MAILSUB"
    px · 2010-10-24 00:35:23 6
  • use screen as a terminal emulator to connect to serial consoles

    Use GNU/screen as a terminal emulator for anything serial console related. screen /dev/tty eg. screen /dev/ttyS0 9600 MacOSX: http://www.macosxhints.com/article.php?story=20061109133825654 Cheat Sheet: http://www.catonmat.net/blog/screen-terminal-emulator-cheat-sheet/ Show Sample Output


    11
    screen /dev/tty<device> 9600
    px · 2010-07-20 09:12:13 37

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Installs pip packages defining a proxy

Remove old unused kernels from Red Hat Enterprise Linux 5 & Fedora 12/13
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Which processes are listening on a specific port (e.g. port 80)
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list files recursively by size

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Limit the transfer rate and size of data over a pipe
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no # comments, blank lines, white space. # can start in any column
The shortest and most complete comment/blank line remover... Any line where the first non-whitespace character is # (ie, indented # comments), and all null and blank lines are removed. Use the alias as a filter: $ noc /etc/hosts or $ grep server /etc/hosts | noc Change to nawk depending awk versions.

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