External IP of Internal Server

Question

I've seen this question, but it doesn't address my current issue (it's about getting the external IP address of the current machine):
Windows command that returns external IP

I'm on a network that has a number of external IP addresses. I need to determine the external address of an internal machine that may use a different external address. Obviously, I could go to a machine outside the network and ping it from there, but how do I do this from inside the network?

I would like this to be incorporated into an automated process, so a DOS command or PowerShell script would be preferred.

Isn't it set using NAT on your router? The machine isn't aware of any external address. Only router is — Ashtray, Sep 13 '13 at 15:24
@Ashtray Is it possible to do something like ping the server via another external server / service? — p.s.w.g, Sep 13 '13 at 15:35
It would be easier to answer if we'd know what are you trying to achieve/test/whatever :) — Ashtray, Sep 13 '13 at 15:37
@Ashtray I want to automatically build a list of IP address(es) that a customer will need to access when we install a particular product on their machine. Some customers are behind a firewall, so we can't determine it from the machine we're installing on (we would already need to know which IP's need to be unblocked). Rather, I'd like our build server to generate the list dynamically by resolving the server names to *external* IP addresses. — p.s.w.g, Sep 13 '13 at 16:13

score 3 · Accepted Answer · answered Sep 13 '13 at 15:37

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I think the only way you're gonna do this is with external services. You can use the system.Net.WebClient Powershell library along with the website http://icanhazip.com, which returns nothing but your external IP address.

$obj = New-Object system.Net.WebClient;
$ip = $obj.downloadString("http://icanhazip.com")

answered Sep 13 '13 at 15:37

trpt4him

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How can I get this to return the IP address of another machine? – p.s.w.g Sep 13 '13 at 15:52
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You'd have to execute it from THAT machine. Or, you could run Powershell on that machine remotely by using PsExec. http://technet.microsoft.com/en-us/sysinternals/bb897553.aspx – trpt4him Sep 13 '13 at 15:54
I agree: you would need to be on the other machine in order to discover its external IP address, so the other question that you cited is relevant. – Scott - Слава Україні Sep 13 '13 at 16:27
@Scott it's not the ip of that machine it's the ip of the network interface of the internet side of the NAT router. not of that machine at all. – barlop Sep 13 '13 at 19:08
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@barlop, the OP said there are multiple external IPs. Presumably different machines could have different external IPs. – trpt4him Sep 13 '13 at 20:30
@Scott If I can find a service like this that I can use to ping another server, e.g. `http://icanhazip.com?target=myserver.mydomain.com`, that would work just fine. – p.s.w.g Sep 13 '13 at 21:48
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Well, if you have a hostname that reliably points to that IP, then you can just use `nslookup` to get the IP. – trpt4him Sep 13 '13 at 23:46
@trpt4him yup `nslookup` is exactly what I needed. – p.s.w.g Sep 24 '13 at 23:29

barlop · Answer 2 · 2022-05-24T17:05:16.783

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ifconfig.me is a bit slow for me at the moment, but this works.

From commandlinefu

curl ifconfig.me

curl ifconfig.me/ip -> IP Adress
curl ifconfig.me/host -> Remote Host
curl ifconfig.me/ua ->User Agent
curl ifconfig.me/port -> Port

Another is

C:\>wget -O abc.a ifconfig.me/ip 2>nul & type abc.a

(obviously you can put that wget line in a bat file so effectively make a shortcut for it)

you have to download wget(a recent one is in/bundled with cygwin) or use curl http://curl.haxx.se/download.html

I'd add, that technically what you are finding is the IP of the external interface of your router / home router / NAT device. So the side of that device opposite to where your computer's plug into it. The side of that device that is facing the wall and connecting to your ISP through the wall. The IP of the network interface that is there.

edited May 24 '22 at 17:05

answered Sep 13 '13 at 19:22

barlop

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as an alternative: [ifcfg.me](http://ifcfg.me) – Eun Nov 28 '14 at 11:37
@Eun the good thing with ifconfig.me/ip was it gave just the IP address no other data to grep. – barlop Nov 28 '14 at 11:48
Should work with ifcfg.me too, just do `curl ifcfg.me`, btw it also supports ftp, nslookup etc. – Eun Nov 28 '14 at 11:53
@Eun oh I see, it detects user agent so chrome returns an html page and curl - an ip. good find – barlop Nov 28 '14 at 12:52

score 0 · Answer 3 · edited Mar 20 '17 at 10:04

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Edit: Scratch that, I got the gateway mixed up with the external IP. I was able to find this one though that has a bunch of good information in it.

I'm sure there has to be an easy way to do it locally but there are just too many variables.

How to get my external ip address over nat from the windows command line

edited Mar 20 '17 at 10:04

Community

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answered Sep 13 '13 at 16:02

Jon

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score 0 · Answer 4 · answered Sep 13 '13 at 18:59

If you can install programs on the other machine, an easy way would be to configure this machine to publish its IP address as a dns entry.

For example http://dyn.com/dns/ (not free) and http://www.noip.com/free/ appear to be two programs that provide this service.

For example, with dyn.com you can install a program which runs as a service on the other machine that will keep updating the dns entry for, as an example, yourname.dyndns.org.

If you want to know the current ip address, then you can just ping yourname.dyndns.org.

In some cases (eg accessing an webserver), you could use the name directly and never need to know the ip address.

score -1 · Answer 5 · edited Sep 20 '15 at 01:41

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I had similar problem so I wrote simple command line tool, you can download OuterIP from sourceforge.

edited Sep 20 '15 at 01:41

Sathyajith Bhat

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answered Jan 04 '14 at 07:36

user286725

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If you read the comments to the accepted answer you'll notice that the this is not the answer the OP was looking for. – Sander Steffann Jan 04 '14 at 09:59
Just a download link is not an answer even if it is useful in solving the question. It's likely to attract downvotes. – fixer1234 Sep 20 '15 at 01:34

External IP of Internal Server

5 Answers5