How to get the primary IP address of the local machine on Linux and OS X? [closed]

Question

I am looking for a command line solution that would return me the primary (first) IP address of the localhost, other than 127.0.0.1

The solution should work at least for Linux (Debian and RedHat) and OS X 10.7+

I am aware that ifconfig is available on both but its output is not so consistent between these platforms.

Answer 1

Use grep to filter IP address from ifconfig:

ifconfig | grep -Eo 'inet (addr:)?([0-9]*\.){3}[0-9]*' | grep -Eo '([0-9]*\.){3}[0-9]*' | grep -v '127.0.0.1'

Or with sed:

ifconfig | sed -En 's/127.0.0.1//;s/.*inet (addr:)?(([0-9]*\.){3}[0-9]*).*/\2/p'

If you are only interested in certain interfaces, wlan0, eth0, etc. then:

ifconfig wlan0 | ...

You can alias the command in your .bashrc to create your own command called myip for instance.

alias myip="ifconfig | sed -En 's/127.0.0.1//;s/.*inet (addr:)?(([0-9]*\.){3}[0-9]*).*/\2/p'"

A much simpler way is hostname -I (hostname -i for older versions of hostname but see comments). However, this is on Linux only.

Answer 2

The following will work on Linux but not OSX.

This doesn't rely on DNS at all, and it works even if /etc/hosts is not set correctly (1 is shorthand for 1.0.0.0):

ip route get 1 | awk '{print $NF;exit}'

or avoiding awk and using Google's public DNS at 8.8.8.8 for obviousness:

ip route get 8.8.8.8 | head -1 | cut -d' ' -f8

A less reliable way: (see comment below)

hostname -I | cut -d' ' -f1

Answer 3

For linux machines (not OS X) :

hostname --ip-address

Answer 4

Solution

$ ip -o route get to 8.8.8.8 | sed -n 's/.*src \([0-9.]\+\).*/\1/p'
192.168.8.16

Explanation

The correct way to query network information is using ip:

• -o one-line output
• route get to get the actual kernel route to a destination
• 8.8.8.8 Google IP, but can use the real IP you want to reach

e.g. ip output:

8.8.8.8 via 192.168.8.254 dev enp0s25 src 192.168.8.16 uid 1000 \   cache

To extract the src ip, sed is the ligthest and most compatible with regex support:

• -n no output by default
• 's/pattern/replacement/p' match pattern and print replacement only
• .*src \([0-9.]\+\).* match the src IP used by the kernel, to reach 8.8.8.8

e.g. final output:

192.168.8.16

Other answers

I think none of the preceding answer are good enough for me, as they don't work in a recent machine (Gentoo 2018).

Issues I found with preceding answers:

• use of positional column in command output;
• use of ifconfig which is deprecated and -- for example -- don't list multple IPs;
• use of awk for a simple task which sed can handle better;
• ip route get 1 is unclear, and is actually an alias for ip route get to 1.0.0.0
• use of hostname command, which don't have -I option in all appliance and which return 127.0.0.1 in my case.

Answer 5

on Linux

hostname -I

on macOS

ipconfig getifaddr en0

---

hostname -I can return multiple addresses in an unreliable order (see the hostname manpage), but for me it just returns 192.168.1.X, which is what you wanted.

Answer 6

Edited (2014-06-01 2018-01-09 2021-07-25 2024-02-19)

From some time ago, I use now newer ip tool. But under bash, I will do simply:

read -r _{,} gateway _ iface _ ip _ < <(ip r g 1.0.0.0)

Then

printf '%-12s %s\n'  gateway $gateway iface $iface ip $ip

gateway      192.168.1.1
iface        eth0
ip           192.168.1.37

From there, the mask is:

while IFS=$' /\t\r\n' read lne lip lmask _; do
    case $lne:$lip in "inet:$ip") masklen=$lmask; break ;; esac
done < <(ip a s dev $iface)

echo Mask is $masklen bits length.

Mask is 24 bits length.

( Note: I've replaced double test: [[ $ip = ... ]] && [[... by case condition, because of efficience and speedness more infos at stringContain!! )

Then if you want to see your mask as an IP:

printf -v mask '%*s' $masklen ''
printf -v mask %-32s ${mask// /1}
printf -v mask %d.%d.%d.%d $((mask=2#${mask// /0},mask>>24)) \
    $((mask>>16&255)) $((mask>>8&255)) $((mask&255))

Then showing all variables:

for var in ip mask gateway masklen iface; do
    printf '%-12s %s\n' $var ${!var}
done

ip           192.168.1.37
mask         255.255.255.0
gateway      192.168.1.1
masklen      24
iface        eth0

Edited (2014-06-01 2018-01-09)

For stronger config, with many interfaces and many IP configured on each interfaces, I wrote a pure bash script (not based on 127.0.0.1) for finding correct interface and ip, based on default route. I post this script at very bottom of this answer.

Intro

As both Os have bash installed by default, there is a bash tip for both Mac and Linux:

The locale issue is prevented by the use of LANG=C:

myip=
while IFS=$': \t' read -a line ;do
    [ -z "${line%inet}" ] && ip=${line[${#line[1]}>4?1:2]} &&
        [ "${ip#127.0.0.1}" ] && myip=$ip
  done< <(LANG=C /sbin/ifconfig)
echo $myip

Putting this into a function:

Minimal:

getMyIP() {
    local _ip _line
    while IFS=$': \t' read -a _line ;do
        [ -z "${_line%inet}" ] &&
           _ip=${_line[${#_line[1]}>4?1:2]} &&
           [ "${_ip#127.0.0.1}" ] && echo $_ip && return 0
      done< <(LANG=C /sbin/ifconfig)
}

Simple use:

getMyIP
192.168.1.37

Fancy tidy:

getMyIP() {
    local _ip _myip _line _nl=$'\n'
    while IFS=$': \t' read -a _line ;do
        [ -z "${_line%inet}" ] &&
           _ip=${_line[${#_line[1]}>4?1:2]} &&
           [ "${_ip#127.0.0.1}" ] && _myip=$_ip
      done< <(LANG=C /sbin/ifconfig)
    printf ${1+-v} $1 "%s${_nl:0:$[${#1}>0?0:1]}" $_myip
}

Usage:

getMyIP
192.168.1.37

or, running same function, but with an argument:

getMyIP varHostIP
echo $varHostIP
192.168.1.37
set | grep ^varHostIP
varHostIP=192.168.1.37

Nota: Without argument, this function output on STDOUT, the IP and a newline, with an argument, nothing is printed, but a variable named as argument is created and contain IP without newline.

Nota2: This was tested on Debian, LaCie hacked nas and MaxOs. If this won't work under your environ, I will be very interested by feed-backs!

Older version of this answer

( Not deleted because based on sed, not bash. )

Warn: There is an issue about locales!

Quick and small:

myIP=$(ip a s|sed -ne '/127.0.0.1/!{s/^[ \t]*inet[ \t]*\([0-9.]\+\)\/.*$/\1/p}')

Exploded (work too;)

myIP=$(
    ip a s |
    sed -ne '
        /127.0.0.1/!{
            s/^[ \t]*inet[ \t]*\([0-9.]\+\)\/.*$/\1/p
        }
    '
)

Edit:

How! This seem not work on Mac OS...

Ok, this seem work quite same on Mac OS as on my Linux:

myIP=$(LANG=C /sbin/ifconfig  | sed -ne $'/127.0.0.1/ ! { s/^[ \t]*inet[ \t]\\{1,99\\}\\(addr:\\)\\{0,1\\}\\([0-9.]*\\)[ \t\/].*$/\\2/p; }')

splitted:

myIP=$(
    LANG=C /sbin/ifconfig  |
        sed -ne $'/127.0.0.1/ ! {
            s/^[ \t]*inet[ \t]\\{1,99\\}\\(addr:\\)\\{0,1\\}\\([0-9.]*\\)[ \t\/].*$/\\2/p;
        }')

My script (jan 2018):

This script will first find your default route and interface used for, then search for local ip matching network of gateway and populate variables. The last two lines just print, something like:

Interface   : en0
Local Ip    : 10.2.5.3
Gateway     : 10.2.4.204
Net mask    : 255.255.252.0
Run on mac  : true

or

Interface   : eth2
Local Ip    : 192.168.1.31
Gateway     : 192.168.1.1
Net mask    : 255.255.255.0
Run on mac  : false

Well, there it is:

#!/bin/bash
runOnMac=false
int2ip() { printf ${2+-v} $2 "%d.%d.%d.%d" \
        $(($1>>24)) $(($1>>16&255)) $(($1>>8&255)) $(($1&255)) ;}
ip2int() { local _a=(${1//./ }) ; printf ${2+-v} $2 "%u" $(( _a<<24 |
                  ${_a[1]} << 16 | ${_a[2]} << 8 | ${_a[3]} )) ;}
while IFS=$' :\t\r\n' read a b c d; do
    [ "$a" = "usage" ] && [ "$b" = "route" ] && runOnMac=true
    if $runOnMac ;then
        case $a in 
            gateway )    gWay=$b  ;;
            interface )  iFace=$b ;;
        esac
    else
        [ "$a" = "0.0.0.0" ] && [ "$c" = "$a" ] && iFace=${d##* } gWay=$b
    fi
done < <(/sbin/route -n 2>&1 || /sbin/route -n get 0.0.0.0/0)
ip2int $gWay gw
while read lhs rhs; do
    [ "$lhs" ] && { 
        [ -z "${lhs#*:}" ] && iface=${lhs%:}
        [ "$lhs" = "inet" ] && [ "$iface" = "$iFace" ] && {
            mask=${rhs#*netmask }
            mask=${mask%% *}
            [ "$mask" ] && [ -z "${mask%0x*}" ] &&
                printf -v mask %u $mask ||
                ip2int $mask mask
            ip2int ${rhs%% *} ip
            (( ( ip & mask ) == ( gw & mask ) )) &&
                int2ip $ip myIp && int2ip $mask netMask
        }
    }
done < <(/sbin/ifconfig)
printf "%-12s: %s\n" Interface $iFace Local\ Ip $myIp \
       Gateway $gWay Net\ mask $netMask Run\ on\ mac $runOnMac

Answer 7

Specific to only certain builds of Ubuntu. Though it may just tell you 127.0.0.1:

hostname  -i

or

hostname -I

Answer 8

You can also get IP version 4 address of eth0 by using this command in linux

/sbin/ip -4 -o addr show dev eth0| awk '{split($4,a,"/");print a[1]}'

Output will be like this

[root@localhost Sathish]# /sbin/ip -4 -o addr show dev eth0| awk '{split($4,a,"/");print a[1]}'
192.168.1.22

Answer 9

Using some of the other methods You may enter a conflict where multiple IP adresses is defined on the system. This line always gets the IP address by default used.

ip route get 8.8.8.8 | head -1 | awk '{print $7}'

Answer 10

This works on Linux and OSX

This will get the interface associated to the default route

NET_IF=`netstat -rn | awk '/^0.0.0.0/ {thif=substr($0,74,10); print thif;} /^default.*UG/ {thif=substr($0,65,10); print thif;}'`

Using the interface discovered above, get the ip address.

NET_IP=`ifconfig ${NET_IF} | grep -Eo 'inet (addr:)?([0-9]*\.){3}[0-9]*' | grep -Eo '([0-9]*\.){3}[0-9]*' | grep -v '127.0.0.1'`

OSX

uname -a

Darwin laptop 14.4.0 Darwin Kernel Version 14.4.0: Thu May 28 11:35:04 PDT 2015; root:xnu-2782.30.5~1/RELEASE_X86_64 x86_64

echo $NET_IF

en5

echo $NET_IP

192.168.0.130

CentOS Linux

uname -a

Linux dev-cil.medfx.local 2.6.18-164.el5xen 1 SMP Thu Sep 3 04:03:03 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux

echo $NET_IF

eth0

echo $NET_IP

192.168.46.10

Answer 11

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

Answer 12

Im extracting my comment to this answer:

ip route get 1 | sed -n 's/^.*src \([0-9.]*\) .*$/\1/p'

It bases on @CollinAnderson answer which didn't work in my case.

Answer 13

Finds an IP address of this computer in a network which is a default gateway (for example excludes all virtual networks, docker bridges) eg. internet gateway, wifi gateway, ethernet

ip route| grep $(ip route |grep default | awk '{ print $5 }') | grep -v "default" | awk '/scope/ { print $9 }'

Works on Linux.

Test:

➜  ~ ip route| grep $(ip route |grep default | awk '{ print $5 }') | grep -v "default" | awk '/scope/ { print $9 }'
192.168.0.114

➜  reverse-networking git:(feature/type-local) ✗ ifconfig wlp2s0
wlp2s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.0.114  netmask 255.255.255.0  broadcast 192.168.0.255
        inet6 fe80::d3b9:8e6e:caee:444  prefixlen 64  scopeid 0x20<link>
        ether ac:x:y:z  txqueuelen 1000  (Ethernet)
        RX packets 25883684  bytes 27620415278 (25.7 GiB)
        RX errors 0  dropped 27  overruns 0  frame 0
        TX packets 7511319  bytes 1077539831 (1.0 GiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

Answer 14

Assuming you need your primary public IP as it seen from the rest of the world, try any of those:

wget http://ipecho.net/plain -O - -q
curl http://icanhazip.com
curl http://ifconfig.me/ip

Answer 15

I have to add to Collin Andersons answer that this method also takes into account if you have two interfaces and they're both showing as up.

ip route get 1 | awk '{print $NF;exit}'

I have been working on an application with Raspberry Pi's and needed the IP address that was actually being used not just whether it was up or not. Most of the other answers will return both IP address which isn't necessarily helpful - for my scenario anyway.

Answer 16

ip addr show | grep -E '^\s*inet' | grep -m1 global | awk '{ print $2 }' | sed 's|/.*||'

Answer 17

The shortest way to get your local ipv4-address on your linux system:

hostname -I | awk '{print $1}'

Answer 18

Primary network interface IP

ifconfig `ip route | grep default | head -1 | sed 's/\(.*dev \)\([a-z0-9]*\)\(.*\)/\2/g'` | grep -oE "\b([0-9]{1,3}\.){3}[0-9]{1,3}\b" | head -1

Answer 19

Not sure if this works in all os, try it out.

ifconfig | awk -F"[ :]+" '/inet addr/ && !/127.0/ {print $4}'

Answer 20

Another ifconfig variantion that works both on Linux and OSX:

ifconfig | grep "inet " | cut -f2 -d' '

Answer 21

I just utilize Network Interface Names, my custom command is

[[ $(ip addr | grep enp0s25) != '' ]] && ip addr show dev enp0s25 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p' || ip addr show dev eth0 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p' 

in my own notebook

[flying@lempstacker ~]$ cat /etc/redhat-release 
CentOS Linux release 7.2.1511 (Core) 
[flying@lempstacker ~]$ [[ $(ip addr | grep enp0s25) != '' ]] && ip addr show dev enp0s25 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p' || ip addr show dev eth0 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p'
192.168.2.221
[flying@lempstacker ~]$

but if the network interface owns at least one ip, then it will show all ip belong to it

for example

Ubuntu 16.10

root@yakkety:~# sed -r -n 's@"@@g;s@^VERSION=(.*)@\1@p' /etc/os-release
16.04.1 LTS (Xenial Xerus)
root@yakkety:~# [[ $(ip addr | grep enp0s25) != '' ]] && ip addr show dev enp0s25 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p' || ip addr show dev eth0 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p'
178.62.236.250
root@yakkety:~#

Debian Jessie

root@jessie:~# sed -r -n 's@"@@g;s@^PRETTY_NAME=(.*)@\1@p' /etc/os-release
Debian GNU/Linux 8 (jessie)
root@jessie:~# [[ $(ip addr | grep enp0s25) != '' ]] && ip addr show dev enp0s25 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p' || ip addr show dev eth0 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p'
192.81.222.54
root@jessie:~# 

CentOS 6.8

[root@centos68 ~]# cat /etc/redhat-release 
CentOS release 6.8 (Final)
[root@centos68 ~]# [[ $(ip addr | grep enp0s25) != '' ]] && ip addr show dev enp0s25 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p' || ip addr show dev eth0 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p'
162.243.17.224
10.13.0.5
[root@centos68 ~]# ip route get 1 | awk '{print $NF;exit}'
162.243.17.224
[root@centos68 ~]#

Fedora 24

[root@fedora24 ~]# cat /etc/redhat-release 
Fedora release 24 (Twenty Four)
[root@fedora24 ~]# [[ $(ip addr | grep enp0s25) != '' ]] && ip addr show dev enp0s25 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p' || ip addr show dev eth0 | sed -n -r 's@.*inet (.*)/.*brd.*@\1@p'
104.131.54.185
10.17.0.5
[root@fedora24 ~]# ip route get 1 | awk '{print $NF;exit}'
104.131.54.185
[root@fedora24 ~]#

It seems like that command ip route get 1 | awk '{print $NF;exit}' provided by link is more accurate, what's more, it more shorter.

Answer 22

I went through a lot of links (StackExchange, AskUbuntu, StackOverflow etc) and came to the decision to combine all the best solutions into one shell script.

In my opinion these two QAs are the best of seen:

How can I get my external IP address in a shell script? https://unix.stackexchange.com/q/22615

How do I find my internal ip address? https://askubuntu.com/a/604691

Here is my solution based on some ideas by rsp shared in his repository (https://github.com/rsp/scripts/).

Some of you could say that this script is extremely huge for so simple task but I'd like to make it easy and flexible in usage as much as possible. It supports simple configuration file allowing redefine the default values.

It was successfully tested under Cygwin, MINGW and Linux (Red Hat).

Show internal IP address

myip -i

Show external IP address

myip -e

Source code, also available by the link: https://github.com/ildar-shaimordanov/tea-set/blob/master/home/bin/myip. Example of configuration file is there, next to the main script.

#!/bin/bash

# =========================================================================
#
# Getting both internal and external IP addresses used for outgoing 
# Internet connections.
#
# Internal IP address is the IP address of your computer network interface 
# that would be used to connect to Internet.
#
# External IP address is the IP address that is visible by external 
# servers that you connect to over Internet.
#
# Copyright (C) 2016 Ildar Shaimordanov
#
# =========================================================================

# Details of the actual implementation are based on the following QA:
#
# How can I get my external IP address in a shell script?
# https://unix.stackexchange.com/q/22615
#
# How do I find my internal ip address?
# https://askubuntu.com/a/604691

# =========================================================================

for f in \
    "$( dirname "$0" )/myip.conf" \
    ~/.myip.conf \
    /etc/myip.conf
do
    [ -f "$f" ] && {
        . "$f"
        break
    }
done

# =========================================================================

show_usage() {
    cat - <<HELP
USAGE
  $( basename "$0" ) [OPTIONS]

DESCRIPTION
  Display the internal and external IP addresses

OPTIONS
  -i  Display the internal IP address
  -e  Display the external IP address
  -v  Turn on verbosity
  -h  Print this help and exit
HELP
    exit
}

die() {
    echo "$( basename "$0" ): $@" >&2
    exit 2
}

# =========================================================================

show_internal=""
show_external=""
show_verbose=""

while getopts ":ievh" opt
do
    case "$opt" in
    i )
        show_internal=1
        ;;
    e )
        show_external=1
        ;;
    v )
        show_verbose=1
        ;;
    h )
        show_usage
        ;;
    \? )
        die "Illegal option: $OPTARG"
        ;;
    esac
done

if [ -z "$show_internal" -a -z "$show_external" ]
then
    show_internal=1
    show_external=1
fi

# =========================================================================

# Use Google's public DNS to resolve the internal IP address
[ -n "$TARGETADDR" ] || TARGETADDR="8.8.8.8"

# Query the specific URL to resolve the external IP address
[ -n "$IPURL" ] || IPURL="ipecho.net/plain"

# Define explicitly $IPCMD to gather $IPURL using another tool
[ -n "$IPCMD" ] || {
    if   which curl >/dev/null 2>&1
    then
        IPCMD="curl -s"
    elif which wget >/dev/null 2>&1
    then
        IPCMD="wget -qO -"
    else
        die "Neither curl nor wget installed"
    fi
}

# =========================================================================

resolveip() {
    {
        gethostip -d "$1" && return
        getent ahostsv4 "$1" \
        | grep RAW \
        | awk '{ print $1; exit }' 
    } 2>/dev/null
}

internalip() {
    [ -n "$show_verbose" ] && printf "Internal: "

    case "$( uname | tr '[:upper:]' '[:lower:]' )" in
    cygwin* | mingw* | msys* )
        netstat -rn \
        | grep -w '0.0.0.0' \
        | awk '{ print $4 }'
        return
        ;;
    esac

    local t="$( resolveip "$TARGETADDR" )"
    [ -n "$t" ] || die "Cannot resolve $TARGETADDR"
    ip route get "$t" \
    | awk '{ print $NF; exit }'
}

externalip() {
    [ -n "$show_verbose" ] && printf "External: "

    eval $IPCMD "$IPURL" $IPOPEN
}

# =========================================================================

[ -n "$show_internal" ] && internalip
[ -n "$show_external" ] && externalip

# =========================================================================

# EOF

Answer 23

Works on Mac, Linux and inside Docker Containers:

$ hostname --ip-address 2> /dev/null || (ifconfig | sed -En 's/127.0.0.1//;s/.*inet (addr:)?(([0-9]*\.){3}[0-9]*).*/\2/p' | awk '{print$1; exit}')

Also works on Makefile as:

LOCAL_HOST := ${shell hostname --ip-address 2> /dev/null || (ifconfig | sed -En 's/127.0.0.1//;s/.*inet (addr:)?(([0-9]*\.){3}[0-9]*).*/\2/p' | awk '{print $1; exit}')}

Answer 24

There's a node package for everything. It's cross-platform and easy to use.

$ npm install --global internal-ip-cli

$ internal-ip
fe80::1

$ internal-ip --ipv4
192.168.0.3

This is a controversial approach, but using npm for tooling is becoming more popular, like it or not.

Answer 25

If you know the network interface (eth0, wlan, tun0 etc):

ifconfig eth0 | grep addr: | awk '{ print $2 }' | cut -d: -f2

Answer 26

ifconfig | grep "inet addr:" | grep -v "127.0.0.1" | grep -Eo '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}'  | head -1

Answer 27

ifconfig $(netstat -rn | grep -E "^default|^0.0.0.0" | head -1 | awk '{print $NF}') | grep 'inet ' | awk '{print $2}' | grep -Eo '([0-9]*\.){3}[0-9]*' 

Answer 28

For linux, what you need is this command:

ifconfig $1|sed -n 2p|awk '{ print $2 }'|awk -F : '{ print $2 }'

type this in your shell and you will simply know your ip.

Answer 29

This is easier to read: ifconfig | grep 'inet addr:' |/usr/bin/awk '{print $2}' | tr -d addr:

Answer 30

If you have npm and node installed : npm install -g ip && node -e "const ip = require('ip'); console.log(ip.address())"