Different ways to get the IP address from a Linux box

Question

I'm curious and I want to know all different methods for getting the IP address from a Linux box, I know ifconfig works well, but wondering if there are any other methods to use to obtain the ip address?

Answer 1

One way would be:

ip address list

Answer 2

To find the external IP of a box (behind a NAT firewall for instance) try this one-liner:

curl icanhazip.com

So useful and so quick!

Answer 3

The ip tool is quite handy and can give you a bunch of methods for IP address determination and much more.

Quick exmaples:

ip addr show dev wlan0
ip route list | grep -w src | awk '{print "device:",$3, "address:",$9}'

Answer 4

I've used

hostname -i

But honestly I shouldn't because this relies on the /etc/hosts file of the machine and not the actual IP address.

Answer 5

You can use ping if you know the network interface. (eth0, eth1, wlan0, etc.)

ping -I eth0 www.google.com
ping [-I interface]

from 10.1.1.4

Answer 6

The following command will list all IP addresses

ip addr show

The output from ifconfig does not always show secondary addresses on interfaces which do not have a named alias, such as those added by "ip addr add"