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A "Web 2.0" domain name generator and look for register availability
You would need pwgen installed first, on ubuntu you can get it by apt-get $ sudo apt-get install pwgen

Find the package that installed a command

How to pull out lines between two patterns
This command will display all lines between 2 patterns: word-a and word-b useful for grepping command outputs from file

generate random mac address

Sharing file through http 80 port
From the other machine open a web navigator and go to ip from the machine who launch netcat, http://ip-address/ If you have some web server listening at 80 port then you would need stop them or select another port before launch net cat ;-) * You need netcat tool installed

Wait for file to stop changing
This loop will finish if a file hasn't changed in the last 10 seconds. . It checks the file's modification timestamp against the clock. If 10 seconds have elapsed without any change to the file, then the loop ends. . This script will give a false positive if there's a 10 second delay between updates, e.g. due to network congestion . How does it work? 'date +%s' gives the current time in seconds 'stat -c %Y' gives the file's last modification time in seconds '$(( ))' is bash's way of doing maths '[ X -lt 10 ]' tests the result is Less Than 10 otherwise sleep for 1 second and repeat . Note: Clever as this script is, inotify is smarter.

Find number of computers in domain, OU, etc .

Block all IP addresses and domains that have attempted brute force SSH login to computer
Searches all log files (including archived bzip2 files) for invalid user and PAM authentication errors, both of which are indicative of brute force attempts at logging into computer. A list of all unique IP addresses and domain names is appended to hosts.deny. The command (and grep error messages) will work on Mac OS X 10.6, small adjustments may be needed for other OSs.

See system users

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


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