Unix Tutorials

Linux iptables and ip6tables examples

Linux iptables is a user-space application program that allows a system administrator to configure the tables provided by the Linux kernel firewall (implemented as different read more

How to kill unresponsive ssh session using escape sequence

Sometime ssh shell become unresponsive when left for too long. It is little annoying to close the terminal to kill the ssh session. To kill read more

How to use nc (netcat) to print headers sent by a browser

Unix utility nc (netcat) is a pretty handy utility for many network tasks. One such use is to see what headers are being sent by read more

Python/Perl/Unix one liners

Here are some cool python one liners. Parse apache log using python: print 5th field python -c “import csv,sys;f=csv.reader(sys.stdin, delimiter=’ ‘); print ‘\n’.join([r[5] for r read more