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 5
  • Used to verify if Network Time Protocol daemon is working properly. Show Sample Output


    4
    ntpq -p
    KoRoVaMiLK · 2010-09-14 07:39:20 5
  • 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 5
  • 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 8
  • 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 6
  • 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 32
  • 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 7
  • 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 5
  • 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 5

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Find top 5 big files
zsh: list of files sorted by size, greater than 100mb, head the top 5. '**/*' is recursive, and the glob qualifiers provide '.' = regular file, 'L' size, which is followed by 'm' = 'megabyte', and finally '+100' = a value of 100

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Show the UUID of a filesystem or partition
Shows the UUID of the given partition (here /dev/sda7). Doesn't need to be root.

Make a ready-only filesystem ?writeable? by unionfs
First look into /etc/modules if you have unionfs (or squashfs) support. If not, add the modules. UnionFS combines two filesystems. If there is a need to write a file, /tmp/unioncache will be used to write files (first create that directory). Reads will be done where the file is found first. http://tldp.org/HOWTO/SquashFS-HOWTO/creatingandusing.html

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

View online pdf documents in cli
Probably will not work very well with scanned documents.

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

Get disk quota usage openvz using vzlist
OpenVZ: Get disk quota usage for your VEID

Squish repeated delimiters into one
This can be particularly useful used in conjunction with a following cut command like $echo "hello::::there" | tr -s ':' | cut -d':' -f2 which prints 'there'. Much easier that guessing at -f values for cut. I know 'tr -s' is used in lots of commands here already but I just figured out the -s flag and thought it deserved to be highlighted :)

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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