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I am logged in to a remote Windows Server machine and am trying to attach it to a VPN for a LAN that I am also connected to locally from another Windows machine using Remotr Desktop. I can connect the remote machine to the VPN but when I do so, I lose my remote desktop connection. I am now in a situation where I know/think that the remote machine is on my LAN, but do not know what its current IP is and can therefor not connect to it again.

I do not have any control over the infrastructure, all I have is a remote machine that I do control, and another machine that I also control that is connected to the same LAN as I'm trying to get the remote machine on using the existing VPN.

What tools are available for Windows to allow me to locate the machine on my LAN again? I am imagining that there must be a tool that broadcasts the machines new IP using multicast, or tries to log in to a server component running somewhere with a know IP. Effectively, I am looking for some software that I can run on my remote machine, as well as my local machine, to allow me to discover the new IP address (on the LAN) assigned to the remote machine after connecting to the VPN.

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closed as not constructive by Brent Pabst, Bryan, HopelessN00b, rnxrx, Michael Hampton Sep 11 '12 at 6:43

As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance.If this question can be reworded to fit the rules in the help center, please edit the question.

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Sorry, but this question really doesn't make any sense whatsoever in its current form. –  Dan Sep 6 '12 at 11:01
    
Edited to clarify, please let me know if it still isn't clear what the problem I am trying to solve is. –  user134918 Sep 6 '12 at 11:06
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It may just be me, but I just can't follow your explanation. Can you draw a diagram or label the computers or something. It would help if you included OS's and products, too. –  Dan Sep 6 '12 at 11:08
    
Edited again. I really cannot make it more clear what I'm attempting to accomplish than this. –  user134918 Sep 6 '12 at 11:13
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@user134918 like Chloe said, you really need to label the machines; it's hard to follow what you're describing. –  gravyface Sep 6 '12 at 11:22

3 Answers 3

Not sure I understand your question, but this short comment you made seems to explain the problem fairly well. (Maybe you should replace your question with that comment?)

The logs on your VPN endpoint will provide you the information you need. If you need to automate it so that you don't need to go checking logs for the IP it uses each time it connects, you will likely need to statically assign an IP as the remote PC connects to your LAN.

Without further information on the VPN endpoint you have on your LAN, it's difficult to give a better answer. Guessing that you have tagged the post with Windows, one might assume you are using RRAS, in which case what you want to achieve is possible.

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Yeah, something like that. Would be just stellar if the asker would just take a step back and explain what he's trying to do. When it gets this opaque, 9 times out of 10 you're doing something that's much more easily solved with another technique. –  gravyface Sep 6 '12 at 11:54
    
@Bryan, this would all be great if I had access to any of that, but as I've mentioned before - it is not "my" network and I cannot access any logs related to the VPN, DHCP or similar. I need a tool that allows me to find the machine when it's on the LAN without involving admin access to the infrastructure in between. –  user134918 Sep 6 '12 at 12:04
    
@user134918 So which of these networks are you the systems admin for? –  Bryan Sep 6 '12 at 18:36
    
@Bryan, I am not a sysadmin, I am a humble user trying to get some work done ... –  user134918 Sep 7 '12 at 12:55
    
What you should do then, is contact your company's IT support, as the systems admins will know far more about the network than anyone here. –  Bryan Sep 7 '12 at 21:31

Is the firewall running on the workstation? That affects what can discover it.

Look on the DHCP server of the remote network to view what is registered.

Assign a static IP to the remote machine.

Use nmap to scan the remote network block.

Those are the first ideas I would consider,...

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Unfortunately, I do not own the infrastructure this is running in, and I do not have access to those systems. I can install applications on the remote machine that I'm attaching to a VPN, and I am connected to the VPN from another machine that I also control, but that is the extent of it. –  user134918 Sep 6 '12 at 11:01
    
@user134918 Have you tried asking the systems administrator? –  Bryan Sep 6 '12 at 11:20

Have you tried nslookup?

As in:

nslookup [hostname]

If the machine is set to automatically register in DNS (as it probably should be), nslookup will return the machine's IP for its VPN connection.

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