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I have a shared PC at a remote place on the LAN. I usually work on it using remote desktop connection. Sometimes the IP address of the PC gets changed when someone accidentally or intentionally unplugs and re-plugs the ethernet cable. In that case, it is necessary to go to the PC physically to get the new IP which sometimes is inconvenient for me.

Is there any setting that I can make on the PC so that I can find the new IP address from some other machine? The OS installed is Ubuntu on the shared computer and I have root access to it.

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Is the IP address NATed or are you VPNing to the network? If VPNing you might be able to get to the computer via hostname. – Snowburnt Mar 29 '13 at 16:07
There are dozens of options that allow you to have a dynamic dns by running a small background application on said machine. – Ramhound Mar 29 '13 at 16:58

Run DIG on Linux or nslookup on Windows with the computer name, to look up the IP address.

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nslookup also exists in linux. – Davidw Mar 30 '13 at 6:18

If you are connecting to the remote computer via an internal IP address... in other words, you and the remote computer are both on the same LAN, then you should actually go into the router's administration panel, into the DHCP reservation table, and have that computer always be assigned the same IP address by it's MAC address. That way, regardless of how often it is disconnected, it will always be assigned the same internal IP address by the router.

If you are connecting to this remote computer via the internet, then I would follow these instructions at to set it up for proper handling of a Dynamic IP address. Yes, it would SEEM like you shouldn't need this, however I can tell you from experience that after you set up with a free DynamicDNS provider (like or even though you are on the same LAN, you can still connect to your new domain, rather than an IP address. That means if you set up an account with, and you created the domain there of, after installing the DynDNS linux client and settings on the Ubuntu machine, you would simply have to connect to instead of the internal IP address... and it would work regardless of any change in that internal IP address.

Of course, combining both solutions is ideal... reserving the Internal IP address in the DHCP reservation table, and using a Dynamic IP service.

I have a home server I like to access on the road. I use a dynamic DNS service like this. And regardless of whether I am on the LAN or out of the house, I still use the same account subdomain to remote in to that computer... and it works just fine.

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You need to reserve the IP of machine going forward, you can use arp –a to list the ARP table and locate the IP if it’s up.

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I am sorry but I could not get you. – Shashwat Kumar Mar 29 '13 at 15:54
For ARP look into RFC826 and on your router it’s connected to so the IP will never change then. – Ben Lavender Mar 29 '13 at 16:36

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