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Get your local IP regardless of your network interface

Terminal - Get your local IP regardless of your network interface
ifconfig|sed '/inet/!d;/127.0/d;/dr:\s/d;s/^.*:\(.*\)B.*$/\1/'
2010-12-01 21:08:29
User: marssi
Functions: ifconfig sed
Get your local IP regardless of your network interface

Shows only IP-addresses of ifconfig except

I fixed the script to work on more systems and configs

short info

/inet/!d; #grep inet

/127.0/d; # grep -v 127.0

/dr:\s/d; # grep -v dr:

s/^.*:\(.*\)B.*$/\1/ # remove everything exept between : and B


There are 2 alternatives - vote for the best!

Terminal - Alternatives
{ if (/^[A-Za-z0-9]/) { interface=$1; next } else { if (/inet [Aa][d]*r/) { split($2,ip,":") } else { next } } print interface"\t: "ip[2] }
2010-12-14 15:38:25
User: gismo82
Tags: ifconfig awk

Shows the interface and the ip-address

ifconfig | sed -ne 's/^.*inet \(addr:\)*\([^ ]*\).*/\2/;te' -e 'd;:e' -e '/^127\./d;p'
2010-12-05 17:14:57
User: dramaturg
Functions: ifconfig sed
Tags: ifconfig sed

This also works on non-Linux machines. If you have GNU sed you can do it more elegantly:

ifconfig | sed -n 's/^\s*inet \(addr:\)\?\([^\s]*\) .*/\2/;T;/^127\./d;p'
ifconfig | grep -o "inet [^ ]*" | cut -d: -f2
2010-12-06 10:36:52
User: dooblem
Functions: cut grep ifconfig
Tags: ifconfig grep cut

This is what we use.

You can grep -v if you wish.

ifconfig | grep "inet\ " | grep -v "127.0" | sed -e 's/inet\ addr://g' | sed -e 's/Bcast:/\ \ \ \ \ \ \ /g' | cut -c 1-29 | sed -e 's/\ //g'

Know a better way?

If you can do better, submit your command here.

What others think

Nice, this is much better than my command, though a little cryptic to a sed newbie like myself.

Comment by LinuxMan 253 weeks ago

On my Debian PCs the marssi method doesn't report the local IP but the Bcast

Comment by rollopack 253 weeks ago

I tested it on debian lenny and sid, both works for me.

If you wanna try this one on your system rollopack?

ifconfig|sed '/inet/!d;/127.0/d;/dr:\s/d;s/^.*:\(.*\)B.*$/\1/'

The problem with my suggestion is that if you use it in a script and put it in a variable, the variable might have extra whitespaces in the end.

Comment by marssi 253 weeks ago

ifconfig|sed '/inet/!d;/127.0/d;/dr:\s/d;s/^.*:\(.*\)\s.*$/\1/'

Which is the Bcast address.

Comment by carlesso 253 weeks ago

ifconfig|sed '/inet/!d;/127.0/d;/dr:\s/d;s/^.*:\(.*\)B.*$/\1/' Ok - IP address

ifconfig|sed '/inet/!d;/127.0/d;/dr:\s/d;s/^.*:\(.*\)\s.*$/\1/' Fail - Bcast address

Comment by rollopack 252 weeks and 3 days ago


Comment by marssi 252 weeks and 1 day ago

Your point of view

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