Comments on: Read UNIX / Linux System IP Address In a Shell Script

By: Gaveen

Gaveen — Mon, 13 Jun 2011 11:59:19 +0000

Or you could run:

hostname -I

By: Chris Browne

Chris Browne — Wed, 08 Jun 2011 09:24:58 +0000

Yeah, because lynx/curl execute the returned website. That’s how they work. Didn’t you know? They take what whatsmyip.org respond with, pass it into a system() call and it gets executed. Yup. And when you’re executing lynx as your user (which nobody suggested to do otherwise) rm -rf / is still able to wipe out your hard drive, because well… linux just doesn’t have a permissions system.

ifconfig on the other hand, an administrator’s tool which sends a lot of information about your network interfaces to your shell, potentially sending the result in an email if the script is run from cron; well, that’s just brilliant. So much more secure. I’d definitely recommend using ifconfig. Yup. Blast a load of intimate hardware details across SMTP, way more secure than fetching a HTML response from a web server that contains nothing but your IP address.

Seriously, though, if you’re gonna get angry at people for lax security practices at least have a clue what you’re talking about first.

By: Danny Walker

Danny Walker — Fri, 13 May 2011 00:39:25 +0000

You can also do it in cygwin (you have to use Microsoft’s ipconfig command):

ipconfig | grep ‘IP Address’ | grep -v 0.0.0.0 | awk ‘{ print $15}’
($15 signifies the 15th word – the dots are words too!)

Therefore, to mimic cygwin’s default prompt, use:

export PS1=”\[\e]0;\w\a\]\n\[\e[32m\]\u@`ipconfig | grep ‘IP Address’ | grep -v 0.0.0.0 | awk ‘{ print $15}’` \[\e[33m\]\w\[\e[0m\]\n\$”

This work for me, but it’s a bit system specific. For example, if you have additional network interfaces, you may have to grep -v any others that might be returned.

Dan

By: vio

vio — Mon, 25 Apr 2011 11:33:05 +0000

hostname -I

By: ulysses768

ulysses768 — Mon, 21 Feb 2011 15:59:22 +0000

This can be done exclusively in bash, if you’re interested in shaving a ms or two.
IP=`ifconfig`
IP=${IP#*inet addr:}
IP=${IP%% *}

By: neha kamra

neha kamra — Tue, 17 Aug 2010 05:59:12 +0000

Can anyone send me the simple script with explanation to find the ip address…as i am new to this

thanx

By: foo bar

foo bar — Mon, 18 Jan 2010 12:50:40 +0000

OMFG, guys, please, you *do* realize anybody can hack into whatismyip.org and INSTANTLY gain access to your boxes ?!!!! And you’re not even using HTTPS – so any monkey in the middle can 0wn your boxes too !!!!
Are you dumb enough to run those lynx/curl scripts as root as well ???

NEVER EVER put this much trust into 3rd party systems, or you WILL get screwed !

it would be funny watching you after whatismyip.org returns `rm -rf /`

use ifconfig / ip show… and don’t be so freaking lazy

By: Marko Rauhamaa

Marko Rauhamaa — Tue, 24 Nov 2009 10:03:21 +0000

On linux:

hostname -i

By: Mika Marttila

Mika Marttila — Thu, 08 Oct 2009 14:14:42 +0000

Thanks! My virtual Ubuntu server is having problems keeping the same IP from DHCP. I need it to start bind my Django app for whole network so this tip came in handy.

By: Aaron Kushner

Aaron Kushner — Wed, 13 May 2009 21:37:04 +0000

@mohan, you can have multiple separators and not have to rerun awk.
@paul, do you like yours because it has a sed abomination in it? Make it simple!

ifconfig eth0 | awk -F”[: ]+” ‘NR==2 {print $4}’

By: Paul Colby

Paul Colby — Tue, 10 Feb 2009 07:01:20 +0000

My current favourite: ifconfig | sed -n -e 's/:127\.0\.0\.1 //g' -e 's/ *inet addr:$[0-9.]\+$.*/\1/gp' ;)

By: PC Thoughts

PC Thoughts — Tue, 10 Feb 2009 06:53:16 +0000

Finding the local IP address with ifconfig and sed…

There are many ways to determine local IP addresses on Linux platforms. The almost always involve piping ifconfig into a number of grep, awk, cat, and/or tr commands.

Well, my new favorite approach is to pipe ifconfig into a single sed command :)
if…

By: Alan Haggai Alavi

Alan Haggai Alavi — Wed, 26 Nov 2008 14:16:30 +0000

curl whatismyip.org does the same too. No need of extra parametres. :-)

By: Mohan

Mohan — Wed, 27 Feb 2008 14:33:46 +0000

This should do the work

ifconfig eth0| awk ‘NR==2 {print $2}’| awk -F: ‘{print $2}’

By: Oscar

Oscar — Fri, 01 Feb 2008 21:42:56 +0000

@the suggestion of using whatsmyip.

That is a great idea, but if you’re looking to find your ip address on a box that has no internet access then that would not work and the original script(s) should always work. If you’re on a private lan for example with no web access then you can’t see whatsmyip, or ipchicken, etc.

This quick how-to is not so much on how to find your external IP address, but more on the actual address your system has been assigned either DHCP, or statically.

By: igor

igor — Wed, 30 Jan 2008 18:18:29 +0000

if you use a different locale, consider this version for linux:

LC_ALL=C ifconfig | grep ‘inet addr:’| grep -v ’127.0.0.1′ | cut -d: -f2 | awk ‘{ print $1}’

By: lex

lex — Fri, 18 Jan 2008 22:36:23 +0000

@Clue
no. for as far as I know you’ll always need some external server to ‘see’ who you are.
But if someone knows another way to do this, the n please let me know.

By: TJB

TJB — Wed, 16 Jan 2008 18:41:08 +0000

Dude, you just saved me 15 minutes of relearning awk and the like just to pull out the IP addy. Double thanks!

By: Clue

Clue — Tue, 18 Dec 2007 00:52:41 +0000

Hi there,

I’m new to all this and I was wondering, how do those websites get our IP and is there not a shell script that can be written to find out your public IP depending on your private IP without having to use these external websites?

By: Michael Gauthier

Michael Gauthier — Thu, 15 Jun 2006 03:24:00 +0000

If you don’t have lynx installed and want to use wget without messy temporary files, you can use:

wget -qO – http://whatismyip.org/