Shell Command for Getting IP Address?

Question

Is there a bash command to find the IP address for an Ubuntu box? I need to find the IP address so I can ssh into the machine later.

Answer 1

/sbin/ifconfig -a

Answer 2

If you have an internal address in use, checking

curl http://myip.dnsomatic.com

might be a good idea on unix shells.
Or, just plonk that URL into your browser.

---

If you get a different answer from the "ifconfig -a" result,
the ifconfig gave your internal address -- which will probably not work from outside.

---

Even if all seems fine, you could have a firewall in place that will disallow incoming ssh connections.
At which time you should try the port of interest from a browser on the machine at,

http://www.canyouseeme.org/

That will confirm connectivity through,

• external IP address (showing it to you on that page)
• NAT, Port Forwards
• Firewalls

Answer 3

You can use:

/bin/ip addr

Answer 4

/sbin/ifconfig|grep inet|head -1|sed 's/\:/ /'|awk '{print $3}'

If you need your internal adress append your interface after ifconfig, e.g.

 /sbin/ifconfig eth0|grep inet|head -1|sed 's/\:/ /'|awk '{print $3}'

Answer 5

If you are behind a NAT, and need the public IP, use this:

wget -q -O - checkip.dyndns.org|sed -e 's/.Current IP Address: //' -e 's/<.$//'

taken from: http://www.go2linux.org/what-is-my-public-ip-address-with-linux

Answer 6

 curl icanhazip.com

tee hee!

From http://www.commandlinefu.com/commands/view/2966/return-external-ip

Answer 7

If you need to find out what the IP address of your router, you could run this command.

dig +short myip.opendns.com @208.67.222.222 @208.67.220.220

If you are using OpenDNS for your dns server, you could shorten it to:

dig +short myip.opendns.com

You could also use this command.

curl http://myip.dnsomatic.com

Answer 8

The simplest way to go about it is probably

ifconfig eth0

assuming the machine has a single IP address on the default wired interface - you might need

ifconfig wlan0

if it's on WiFi.

Answer 9

ip address show scope link

It will show you the IP address of living - has link - interfaces. But it is not a bash command. Bash has no ability to know about IP and network at all.

Answer 10

What I understand is you want to connect a remote ubuntu machine which has dynamic ip. Go dyndns.org site and open a free account. Then on the remote machine you need to install a dynamic ip tool.

sudo aptitude install dyndns-client

so you can ssh remote machine via

ssh username@yourdynamicnamealias.dyndns.org

So after configuration you will never need the remote machine ip address.

Answer 11

I once golfed the extraction of IP address on Linux:

http://www.catonmat.net/blog/golfing-the-extraction-of-ip-addresses-from-ifconfig/

Answer 12

/bin/hostname -i

Answer 13

If you have multiple interfaces, could be useful to specify which one you want IP. if you want IPV4 address of interface 'eth0':

ip addr show dev eth0 | grep "inet " | awk '{ print $2 }' 

if you want IPV6 address of interface 'eth0':

ip addr show dev eth0 | grep "inet6 " | awk '{ print $2 }' 

if you want to search for an IP between two common interfaces of a laptop, wlan0 and eth0:

CURRENT_IP=''
for INTERFACE in wlan0 eth0; do
    if [ -z $CURRENT_IP ]; then
        CURRENT_IP=$(ip addr show dev $INTERFACE | grep "inet " | awk '{ print $2 }')
    fi
done