How do I find my IP Address from the command line?

Question

I know you can do ifconfig | grep inet, but that shows you several IPv4 addresses. How do I get the specific one for SSHing et al?

Answer 1

Local IP address

For wireless: Use ipconfig getifaddr en1

For ethernet: Useipconfig getifaddr en0.

ipconfig getifaddr en0 is default for the Wi-Fi network adapter

Public IP address

dig -4 TXT +short o-o.myaddr.l.google.com @ns1.google.com

Output, e.g.:

172.79.136.120

Command explanation

The command you provided, dig -4 TXT +short o-o.myaddr.l.google.com @ns1.google.com, is a command-line instruction that uses the dig utility to perform a DNS (Domain Name System) lookup. Let's break down the components of the command:

• dig: dig stands for "domain information groper," and it is a command-line tool commonly available on Unix-like systems for querying DNS servers.

• -4: This option specifies that the command should use IPv4 protocol for the DNS lookup. It ensures that the query is sent using IPv4 instead of IPv6.

• TXT: This indicates the type of DNS record being requested. In this case, the command is asking for the TXT record.

• +short: This option is used to display only the relevant information from the DNS response, providing a concise output.

• o-o.myaddr.l.google.com: This is the hostname used for the DNS lookup. It is a special hostname that Google uses to provide information about the IP address from which the DNS query originates.

• @ns1.google.com: This specifies the DNS server to which the query is sent. In this case, it is set to ns1.google.com, which is one of Google's public DNS servers.

When you run this command, it queries the ns1.google.com DNS server for the TXT record associated with o-o.myaddr.l.google.com. The response will contain the TXT record, which typically includes information about the IP address of the client making the DNS query. The +short option ensures that only the relevant information is displayed, making it easier to read the output.

Answer 2

The following works for me on 10.8 and on 10.10 Yosemite.

ifconfig | grep "inet " | grep -Fv 127.0.0.1 | awk '{print $2}' 

If you find the above gives you more than one answer, save the following to a script, and run it instead

ip_address.sh

#!/usr/bin/env bash
dumpIpForInterface()
{
  IT=$(ifconfig "$1") 
  if [[ "$IT" != "status: active" ]]; then
    return
  fi
  if [[ "$IT" != " broadcast " ]]; then
    return
  fi
  echo "$IT" | grep "inet " | grep -v 127.0.0.1 | awk '{print $2}'
}
main()
{
snagged from here: https://superuser.com/a/627581/38941
DEFAULT_ROUTE=$(route -n get 0.0.0.0 2>/dev/null | awk '/interface: / {print $2}')
  if [ -n "$DEFAULT_ROUTE" ]; then
    dumpIpForInterface "$DEFAULT_ROUTE"
  else
    for i in $(ifconfig -s | awk '{print $1}' | awk '{if(NR>1)print}')
    do 
      if [[ $i != "vboxnet" ]]; then
        dumpIpForInterface "$i"
      fi
    done
  fi
}
main

Answer 3

Typing curl ifconfig.me in Terminal will give your public IP address

Answer 4

I've got this set up in an .aliases dotfile for frequent ip lookup:

alias ip="dig +short myip.opendns.com @resolver1.opendns.com"
alias localip="ipconfig getifaddr en0"

Answer 5

You can do the following:

Type ifconfig or ifconfig -a. This command shows you the list of interfaces along with their IP and MAC addresses (the latter one only if applicable). You can also type ifconfig en0 or ifconfig en1 for the configuration of a particular interface only (as someone said in their answers, en0 is typically the wired Ethernet while en1 is the WiFi interface).

As an alternative, netstat -i will list all interfaces and will show you the IP addresses you have assigned to each of them.

Typically, when you have SSH daemon running on a box, it will listen on all available interfaces, ie. you can use any IP address that's configured on your machine to connect to that machine via SSH (this, obviously, subject to Firewall rules). If you're after what the OS calls a Primary interface and primary IP address, you can use the scutil command like this:

MacBook:~ scutil
> show State:/Network/Global/IPv4
<dictionary> {
  PrimaryInterface : en0
  PrimaryService : C0550F84-5C07-484F-8D62-C8B90DC977D8
  Router : 10.103.4.1
}
> show State:/Network/Interface/en0/IPv4
<dictionary> {
  Addresses : <array> {
    0 : 10.103.4.234
  }
  BroadcastAddresses : <array> {
    0 : 10.103.4.255
  }
  SubnetMasks : <array> {
    0 : 255.255.255.0
  }
}

Please note, that the above, even though is a command-line command, is also interactive (so you run scutil and then enter its own commands into it). The first show command tells you the name of the primary interface for the OS (i.e. this will be the one on top of the list in your System Preferences / Network Preferences window), as well as the IP address of your default router. The second show command takes State:/Network/Interface/<ifname>/IPv4 argument (in this case, en0) and gives you the IP addresses assigned to it. You're looking for the address in the Addresses array, the other two entries are broadcast addresses and the netmasks.

Hope that helps, but if anything is not clear, let me know.

Answer 6

To find your Mac's current internal IP address, run:

ifconfig -l | xargs -n1 ipconfig getifaddr

This is basically equivalent to ipconfig getifaddr en0, but more reliable! en0 is not always the current network interface!

^{Thank you to @epylinkn in the comments of another answer for this hint. I'm posting it here so it's more visible; I initially missed it myself.}

Answer 7

To get the IP address of your computer facing the Internet, here is a working receipe:

if=`netstat -nr | awk '{ if ($1 ~/default/) { print $6} }'`
ifconfig ${if} | awk '{ if ($1 ~/inet/) { print $2} }'

It should work even when you have multiple interfaces active, even when you have interfaces you don't know which one is actually the default gateway.

Answer 8

Just for the record, you can make a bash script with the following content which gives you your external IP address

#!/bin/bash    
wget -qO - http://ipecho.net/plain; echo

Answer 9

This answer work on both mac and linux:

ifconfig | grep -E "([0-9]{1,3}\.){3}[0-9]{1,3}" | grep -v 127.0.0.1 | head -1 | awk '{ print $2 }'