Commands by KoRoVaMiLK (9)

  • These are my favourite switches on pwgen: -B Don't include ambiguous characters in the password -n Include at least one number in the password -y Include at least one special symbol in the password -c Include at least one capital letter in the password It just works! Add a number to set password length, add another to set how many password to output. Example: pwgen -Bnyc 12 20 this will output 20 password of 12 chars length. Show Sample Output


    5
    pwgen -Bnyc
    KoRoVaMiLK · 2012-03-15 14:38:15 4
  • Used to verify if Network Time Protocol daemon is working properly. Show Sample Output


    4
    ntpq -p
    KoRoVaMiLK · 2010-09-14 07:39:20 4
  • Shows useful informations about file descriptors in Squid web proxy Show Sample Output


    -1
    squidclient mgr:info | grep "file desc"
    KoRoVaMiLK · 2010-07-29 17:35:20 4
  • On-the-fly conversion of Unix Time to human-readable in Squid's access.log Show Sample Output


    1
    perl -p -e 's/^([0-9]*)/"[".localtime($1)."]"/e' < /var/log/squid/access.log
    KoRoVaMiLK · 2010-06-22 08:42:40 4
  • Actually 'firefox' is a script that then launches the 'firefox-bin' executable. You need to specify the 'no-remote' option in order to launch remote firefox instead of your local one (this drove me crazy time ago)


    5
    ssh -fY user@REMOTESERVER firefox -no-remote
    KoRoVaMiLK · 2010-06-03 07:24:07 5
  • Useful since "export http_proxy=blahblah:8080" doesn't seem to work with pear Show Sample Output


    -1
    pear config-set http_proxy http://myusername:mypassword@corporateproxy:8080
    KoRoVaMiLK · 2010-05-13 14:44:03 30
  • Simple way to backup your LDAP entries: put this line on your crontab. The -n switch identifies the dbnum you want to backup (alternatively you can use -b suffix. Check man slapcat for your personal switches)


    1
    slapcat -n 1 > /backup/`date "+%Y%m%d"`.ldif
    KoRoVaMiLK · 2010-05-07 15:52:39 6
  • Prints current runlevel and system start time. On older systems it also shows the last init state. Pretty useful on remote systems, pretty useless on local ones :) Show Sample Output


    5
    who -r
    KoRoVaMiLK · 2010-05-05 12:58:09 4
  • This allows you to skip the banner (usually /etc/issue.net) on ssh connections. Useful to avoid banners outputted to your mail by rsync cronjobs.


    1
    ssh -q user@server
    KoRoVaMiLK · 2010-03-24 12:02:55 4

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Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Display Dilbert strip of the day
Requires display. Corrected version thanks to sputnick and eightmillion user.

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" }

move you up one directory quickly
In bash, this turns on auto cd. If a command is just a directory name, it cd's into that directory.

Read random news on the internet
sort -R randomize the list. head -n1 takes the first.

Quick find function
A function that allows you to perform a case-insensitive search in the current directory, and directories in the current directory (but no further), for files containing the first argument anywhere in their names.

Lines per second in a log file

Hypnosis
rather don't depend on those sleepin'pills http://en.wikipedia.org/wiki/Counting_sheep

Rip DVD to YouTube ready MPEG-4 AVI file using mencoder
Rip DVD to YouTube ready AVI file, using MPEG-4 video codec and MP3 audio codec. Resizes to 320x240 and deinterlaces as needed.


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