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 3
  • Used to verify if Network Time Protocol daemon is working properly. Show Sample Output


    4
    ntpq -p
    KoRoVaMiLK · 2010-09-14 07:39:20 2
  • 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 2
  • 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 3
  • 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 4
  • 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 18
  • 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 5
  • 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 3
  • 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 3

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Delete empty, 24-hours-old directories recursively, without consider hidden directories

Extract all 404 errors from your apache accesslog (prefix lines by occurrences number)

Use AWS CLI and JQ to get a list of instances sorted by launch time
Use the AWS CLI tools to generate a list instances, then pipe them to JQ to show only their launch time and instance id. Finally use sort to bring them out in runtime order. Find all those instances you launched months ago and have forgotten about.

Recursively find disk usage, sort, and make human readable (for systems without human-readable sort command)
Recursively find disk usage, sort, and make human readable: * For systems without human-readable sort command * awk, not perl

Count lines of code across multiple file types, sorted by least amount of code to greatest
Gives you a nice quick summary of how many lines each of your files is comprised of. (In this example, we just check .c, .h, .php and .pl). Since we just use wc -l to count, you'll just get a very rough estimate of how many lines of actual code there are. Use a more sophisticated algorithm instead if you need to.

resize all JPG images in folder and create new images (w/o overwriting)
Convert all jpegs in the current directory into ~1024*768 pixels and ~ 150 KBytes jpegs

Look up a unicode character by name
No need for further filedes or substitution for splitting. Simply use read a b

Watch the size of a directory using figlet
You can substitute /home/$USER with any path you like.

Synthesize text as speech
The Festival Speech Synthesis System converts text into sound. Or: links -dump http://youfavoritewebsite.com | festival --tts

Monitor a file's size
use "watch" instead of while-loops in these simple cases


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