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 1
  • Used to verify if Network Time Protocol daemon is working properly. Show Sample Output


    4
    ntpq -p
    KoRoVaMiLK · 2010-09-14 07:39:20 0
  • 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 0
  • 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 1
  • 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 2
  • 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 4
  • 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 2
  • 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 1
  • 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 0

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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

SSH connection through host in the middle

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

Calculating series with awk: add numbers from 1 to 100
"seq 100" outputs 1,2,..,100, separated by newlines. awk adds them up and displays the sum. "seq 1 2 11" outputs 1,3,..,11. Variations: 1+3+...+(2n-1) = n^2 $ seq 1 2 19 | awk '{sum+=$1} END {print sum}' # displays 100 1/2 + 1/4 + ... = 1 $ seq 10 | awk '{sum+=1/(2**$1)} END {print sum}' # displays 0.999023

Run the built in PHP-server in current folder
You must have PHP 5.4.0 or later to be able to run the built in server. This web server is designed for developmental purposes only, and should not be used in production. URI requests are served from the current working directory where PHP was started, unless the -t option is used to specify an explicit document root. If a URI request does not specify a file, then either index.php or index.html in the given directory are returned. If neither file exists, then a 404 response code is returned. If a PHP file is given on the command line when the web server is started it is treated as a "router" script. The script is run at the start of each HTTP request. If this script returns FALSE, then the requested resource is returned as-is. Otherwise the script's output is returned to the browser. Standard MIME types are returned for files with extensions: .css, .gif, .htm, .html, .jpe, .jpeg, .jpg, .js, .png, .svg, and .txt. The .htm and .svg extensions are recognized from PHP 5.4.4 onwards. More information here: http://php.net/manual/en/features.commandline.webserver.php

Use socat to emulate an SMTP mail SERVER
Lots of scripts show you how to use socat to send an email to an SMTP server; this command actually emulates an SMTP server! It assumes the client is only sending to one recipient, and it's not at all smart, but it'll capture the email into a log file and the client will stop retrying. I used this to diagnose what emails were being sent by cron and subsequently discarded, but you can use it for all sorts of things.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Dump android contacts, sms
Crude, but works. Note for security, /data/ will be inaccessible unless your device has been *rooted*. On the other hand, if a device has been rooted, its data is now wide open to anyone with a USB cable and the above "one-liner". `adb` is one of the platform tools in the android SDK. To get SMS messages: $ adb pull /data/data/com.android.providers.telephony/databases/mmssms.db ; sqlite3 -batch

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

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.


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