Commands by bandit36 (3)

  • Periodically loop a command

    You can use this to loop any command to periodically see the output. while true; do [YOUR COMMAND HERE]; sleep [# of seconds]; done; Alternatively, you can put it in a simple shell script to save typing! #/!bin/bash while true; do $1; sleep $2; done; /path/to/script.sh "ifconfig eth0 | grep 'inet addr:'" 60 Show Sample Output


    -5
    while true; do ifconfig eth0 | grep "inet addr:"; sleep 60; done;
    bandit36 · 2009-04-01 19:29:28 19
  • Scan your LAN for unauthorized IPs

    populate the auth.hosts file with a list of IP addresses that are authorized to be in use and when you run this command it will return the addresses that are pingable and not in the authorized list. Can be combined with the "Command line Twitter" command to tweet unauthorized access. Show Sample Output


    1
    diff <(nmap -sP 192.168.1.0/24 | grep ^Host | sed 's/.appears to be up.//g' | sed 's/Host //g') auth.hosts | sed 's/[0-9][a-z,A-Z][0-9]$//' | sed 's/</UNAUTHORIZED IP -/g'
    bandit36 · 2009-03-12 05:28:08 9
  • Backup your hard drive with dd

    This will create an exact duplicate image of your hard drive that you can then restore by simply reversing the "if" & "of" locations. sudo dd if=/media/disk/backup/sda.backup of=/dev/sda Alternatively, you can use an SSH connection to do your backups: dd if=/dev/sda | ssh user@ssh.server.com dd of=~/backup/sda.backup


    16
    sudo dd if=/dev/sda of=/media/disk/backup/sda.backup
    bandit36 · 2009-02-27 20:23:37 29

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check open ports without netstat or lsof

Delete empty directories
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Create cheap and easy index.html file
If your admin has disabled Apache's directory index feature but you want to have a cheap way to enable it for one folder, this command will just create an index.html file with a link to each file in the directory (including the index.html file, which is not ideal but makes the command much simpler). The HTML isn't even remotely compliant, but it could easily be improved on. Also, the command needs to be run each time a file is added or removed to update the index.html file.

Alternative size (human readable) of files and directories (biggest last)
using mb it's still readable;) a symbol variation $ du -ms {,.[^.]}* | sort -nk1

Replicate a directory structure dropping the files
Here is how to replicate the directory structure in the current directory to a destination directory (given by the variable DESTDIR), without copying the files.

Compute running average for a column of numbers
This is an on-line algorithm for calculating the mean value for numbers in a column. Also known as "running average" or "moving average".

Sum size of files returned from FIND

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Store dirs to later be changed to independant of the last directory you were in. Also with managment tools.
Check out: help dirs help pushd help popd -- Cheers!

find files ignoring .svn and its decendents
for when find . -print | grep -v .svn | xargs doesnt cut it.

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