Hide

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.


If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Hide

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

Hide

News

2012-05-20 - test
test
2012-05-20 - test
test
2012-05-20 - test
test
2012-05-20 - Test tweets
YU not working?
Hide

Tags

Hide

Functions

Commands tagged ifconfig

Commands tagged ifconfig from sorted by
Terminal - Commands tagged ifconfig - 38 results
for i in `netstat -rn|egrep -v "Interface|Routing"|awk '{print $5}'`;do ifconfig $i;done
ifconfig | awk '/inet / {sub(/addr:/, "", $2); print $2}'
watch -n 2 -d '/sbin/ifconfig eth0'
ifconfig | awk '/HWaddr/ { print $1, $5 }'
ifconfig | grep HWaddr | awk '{print $1,$5}'
{ if (/^[A-Za-z0-9]/) { interface=$1; next } else { if (/inet [Aa][d]*r/) { split($2,ip,":") } else { next } } print interface"\t: "ip[2] }
ifconfig | grep -o "inet [^ ]*" | cut -d: -f2
2010-12-06 10:36:52
User: dooblem
Functions: cut grep ifconfig
Tags: ifconfig grep cut
-2

This is what we use.

You can grep -v 127.0.0.1 if you wish.

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
0

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|sed '/inet/!d;/127.0/d;/dr:\s/d;s/^.*:\(.*\)B.*$/\1/'
2010-12-01 21:08:29
User: marssi
Functions: ifconfig sed
Tags: ifconfig sed
1

Shows only IP-addresses of ifconfig except 127.0.0.0/8.

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

ifconfig eth0 | grep -o "inet [^ ]*" | cut -d: -f2
ifconfig eth0 | awk '/inet / {print $2}' | cut -d ':' -f2
ifconfig eth0 | grep "inet " | cut -d ':' -f2 | awk '{print $1}'
2010-06-29 00:06:08
User: jaimerosario
Functions: awk cut grep ifconfig
2

I've been using it in a script to build from scratch proxy servers.

ifconfig eth0 | grep 'inet addr' | cut -d ':' -f 2 | cut -d ' ' -f 1
2010-06-26 22:36:21
User: atoponce
Functions: cut grep ifconfig
Tags: ifconfig
2

Simple and easy. No regex, no search and replace. Just clean, built-in tools.

ifconfig -a| awk '/^wlan|^eth|^lo/ {;a=$1;FS=":"; nextline=NR+1; next}{ if (NR==nextline) { split($2,b," ")}{ if ($2 ~ /[0-9]\./) {print a,b[1]}; FS=" "}}'
2010-04-15 04:34:28
User: alf
Functions: awk ifconfig
Tags: ifconfig awk IP
4

Interfaces like lo can be omitted from the beginning, there are probably better ways of doing this, i'm a noob at awk.

ip link show
2010-03-01 20:10:27
User: d34dh0r53
Functions: link
Tags: ifconfig grep
5

I prefer the ip command to ifconfig as ifconfig is supposedly going to be deprecated. Certain IP address aliases can only be seen with the ip command (such as the ones applied by RHCS).

ifconfig | awk '/HWaddr/ { print $NF }'
ifconfig -a| grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'
2010-02-27 14:30:43
User: evenme
Functions: grep ifconfig
Tags: ifconfig grep
3

Get mac address listed for all interfaces.

netstat -in
for i in `lanscan -i | awk '{print $1}'` ; do ifconfig $i ; done
perl -e '$_=`ifconfig eth0`;/\d+.\d+.\d+.\d+ /; print $&,"\n";'
2009-12-05 14:24:48
Functions: perl
0

If you are interested in interfaces other than eth0 you will need to change eth0 to your interface name.

You could use this mammoth to nab the ip4 addresses of all your interfaces

perl -e '@_=`ifconfig -a`; sort(@_); foreach(@_) { /(inet addr\:)(\d+.\d+.\d+.\d+ )/; $_=$2; @uniq=grep($_ ne $prev && (($prev) = $_), @_);} print join "\n",@uniq,"\n"; '

it seems silly to have all this code when the following will work fine

ifconfig -a | grep "inet " | awk -F":" ' { print $2 } ' | cut -d " " -f1

ifconfig -a| awk 'BEGIN{FS="[ :]+"} /Bcast/{print $4}'
ifconfig -a|grep Bcast:|cut -d\: -f2|awk '{print $1}'
ifconfig | awk '/HW/ {print $5}'
2009-11-05 18:00:50
User: Cont3mpo
Functions: awk ifconfig
0

Simple MAC adrress, thanks to ifconfig.

ifconfig eth1 | grep inet\ addr | awk '{print $2}' | cut -d: -f2 | sed s/^/eth1:\ /g
2009-11-03 19:26:40
User: TuxOtaku
Functions: awk cut grep ifconfig sed
2

Sometimes, you don't really care about all the other information that ifconfig spits at you (however useful it may otherwise be). You just want an IP. This strips out all the crap and gives you exactly what you want.

ifconfig -a | perl -nle'/(\d+\.\d+\.\d+\.\d+)/ && print $1'
2009-07-31 09:49:17
User: sneaker
Functions: ifconfig perl
12

works on Linux and Solaris. I think it will work on nearly all *nix-es