Home / ubuntu / Questions / 95910
Accepted
kfmfe04
Asked: 2012-01-17 03:50:35 +0800 CST

Command for determining my public IP?

  • 772

If I check with google, I can see my public IP. Is there something on the Ubuntu command-line which will yield me the same answer?

networking

22 Answers

  1. Best Answer

    If you are not behind a router, you can find it out using ifconfig.

    If you are behind a router, then your computer will not know about the public IP address as the router does a network address translation. You could ask some website what your public IP address is using curl or wget and extract the information you need from it:

    curl -s https://checkip.dyndns.org | sed -e 's/.*Current IP Address: //' -e 's/<.*$//'

    or shorter

    curl https://ipinfo.io/ip
    • 1103

  2. For finding the external ip, you can either use external web-based services, or use system based methods. The easier one is to use the external service, also the ifconfig based solutions will work in your system only if you're not behind a NAT. the two methods has been discussed below in detail.

    Finding external IP using external services

    The easiest way is to use an external service via a commandline browser or download tool. Since wget is available by default in Ubuntu, we can use that.
    To find your ip, use- 

    $ wget -qO- https://ipecho.net/plain ; echo

    Courtesy:

    You could also use lynx(browser) or curl in place of wget with minor variations to the above command, to find your external ip.

    Using curl to find the ip: 

    $ curl https://ipecho.net/plain

    For a better formatted output use:

    $ curl https://ipecho.net/plain ; echo

    A faster (arguably the fastest) method using dig with OpenDNS as resolver:

    The other answers here all go over HTTP to a remote server. Some of them require parsing of the output, or rely on the User-Agent header to make the server respond in plain text. They also change quite frequently (go down, change their name, put up ads, might change output format etc.).

    1. The DNS response protocol is standardised (the format will stay compatible).
    2. Historically DNS services (OpenDNS, Google Public DNS, ..) tend to survive much longer and are more stable, scalable and generally looked after than whatever new hip whatismyip.com HTTP service is hot today.
    3. (for those geeks that care about micro-optimisation), this method should be inherently faster (be it only by a few micro seconds).

    Using dig with OpenDNS as resolver:

    $ dig +short myip.opendns.com @resolver1.opendns.com

111.222.333.444

    Copied from: https://unix.stackexchange.com/a/81699/14497

    Finding external IP without relying on external services

    • If you know your network interface name

    Type the following in your terminal:

    $ LANG=c ifconfig <interface_name> | grep "inet addr" | awk -F: '{print $2}' | awk '{print $1}'

    In the above, replace <interface_name> with the name of your actual interface, e.g: eth0, eth1, pp0, etc...

    Example Usage:

    $ LANG=c ifconfig ppp0 | grep "inet addr" | awk -F: '{print $2}' | awk '{print $1}'
111.222.333.444
    • If you don't know your network interface name

    Type the following in your terminal (this gets the name and ip address of every network interface in your system):

    $ LANG=c ifconfig | grep -B1 "inet addr" |awk '{ if ( $1 == "inet" ) { print $2 } else if ( $2 == "Link" ) { printf "%s:" ,$1 } }' |awk -F: '{ print $1 ": " $3 }'

    Example Usage:

    $ LANG=c ifconfig | grep -B1 "inet addr" |awk '{ if ( $1 == "inet" ) { print $2 } else if ( $2 == "Link" ) { printf "%s:" ,$1 } }' |awk -F: '{ print $1 ": " $3 }'
lo: 127.0.0.1
ppp0: 111.222.333.444

    N.B: Outputs are indicative and not real.

    Courtesy: https://www.if-not-true-then-false.com/2010/linux-get-ip-address/

    UPDATE

    1. LANG=c has been added to ifconfig based usages, so that it always gives the english output, irrespective of locale setting.
    • 415

  3. My favorite has always been :

    curl ifconfig.me

    simple, easy to type.

    You will have to install curl first ;)

    If ifconfig.me is down try icanhazip.com and or ipecho.net

    curl icanhazip.com

    or 

    curl ipecho.net
    • 144

  4. icanhazip.com is my favorite.

    curl icanhazip.com

    You can request IPv4 explicitly:

    curl ipv4.icanhazip.com

    If you don't have curl you can use wget instead:

    wget -qO- icanhazip.com
    • 67

  5. Running my own service, designed to be simple and stupid, ident.me.

    Its API and implementation are documented at https://api.ident.me/

    Examples from the terminal (add https:// for security at the expense of speed):

    curl ident.me
curl v4.ident.me
curl v6.ident.me
    • 55

  6. You could use a DNS request instead of HTTP request to find out your public IP:

    $ dig +short myip.opendns.com @resolver1.opendns.com

    It uses resolver1.opendns.com dns server to resolve the magical myip.opendns.com hostname to your ip address.

    • 52

  7. Amazon AWS

    curl https://checkip.amazonaws.com

    Sample output:

    123.123.123.123

    Also works on browser: http://checkip.amazonaws.com

    I like it because:

    • it returns just the plaintext IP in the reply body, nothing else
    • it is from a well known provider which is unlikely to go offline anytime soon
    • 36

  8. The one i'm using is :

    wget -O - -q icanhazip.com

    Yes, you can have ip :-)

    • 19

  9. For this, STUN was invented. As a client you can send a request to a publicly available STUN server and have it give back the IP address it sees. Sort of the low level whatismyip.com as it uses no HTTP and no smartly crafted DNS servers but the blazingly fast STUN protocol.

    Using stunclient

    If you have stunclient installed (apt-get install stuntman-client on debian/ubuntu) you can simply do:

    $stunclient stun.services.mozilla.com
Binding test: success
Local address: A.B.C.D:42541
Mapped address: W.X.Y.Z:42541

    where A.B.C.D is the IP address of your machine on the local net and W.X.Y.Z is the IP address servers like websites see from the outside (and the one you are looking for). Using sed you can reduce the output above to only an IP address:

    stunclient stun.services.mozilla.com |
    sed -n -e "s/^Mapped address: \(.*\):.*$/\1/p"

    However, your question was how to find it using the command line, which might exclude using a STUN client. So I wonder...

    Using bash

    A STUN request can be handcrafted, sent to an external STUN server using netcat and be post-processed using dd, hexdump and sed like so:

    $echo -en '\x00\x01\x00\x08\xc0\x0c\xee\x42\x7c\x20\x25\xa3\x3f\x0f\xa1\x7f\xfd\x7f\x00\x00\x00\x03\x00\x04\x00\x00\x00\x00' |
    nc -u -w 2 stun.services.mozilla.com 3478 |
    dd bs=1 count=4 skip=28 2>/dev/null |
    hexdump -e '1/1 "%u."' |
    sed 's/\.$/\n/'

    The echo defines a binary STUN request (0x0001 indicates Binding Request) having length 8 (0x0008) with cookie 0xc00cee and some pasted stuff from wireshark. Only the four bytes representing the external IP are taken from the answer, cleaned and printed.

    Working, but not recommended for production use :-)

    P.S. Many STUN servers are available as it is a core technology for SIP and WebRTC. Using one from Mozilla should be safe privacy-wise but you could also use another: STUN server list

    • 14

  10. Type in this exactly, press Enter where indicated:

    telnet ipecho.net 80Enter
    GET /plain HTTP/1.1Enter
    HOST: ipecho.net Enter
    BROWSER: web-kitEnter
    Enter

    This manually submits a HTTP request, which will return your IP at the bottom of a HTTP/1.1 200 OK reply

    Example output:

    $ telnet ipecho.net 80
Trying 146.255.36.1...
Connected to ipecho.net.
Escape character is '^]'.
GET /plain HTTP/1.1
HOST: ipecho.net
BROWSER: web-kit

HTTP/1.1 200 OK
Date: Tue, 02 Jul 2013 07:11:42 GMT
Server: Apache
Expires: Mon, 26 Jul 1997 05:00:00 GMT
Cache-Control: no-cache
Pragma: no-cache
Vary: Accept-Encoding
Transfer-Encoding: chunked
Content-Type: text/html

f
111.222.333.444
0
    • 13