Remote desktop to a computer without screen

Question

I have a laptop with Windows 7 and an older stationary with Windows XP. When I had a screen I set it up for use with remote desktop. I no longer have any screen, and used to connect to it using remote desktop, but that is a few years ago, and LAN details might have changed. When I connect the old computer to the network and boot it up, I cannot see it in the network browser, I don't know its name, its network group name or its IP address.

How can I sniff the network to discover it (should I use a cross-over cable directly?) and get back to using remote desktop?

Answer 1

The best solution would be to borrow a monitor and attach it to the XP computer long enough to get it going and verify that it is working OK.

Do you have a Hi-Def TV? Does it have a VGA port on it? You could use that for a monitor.

Answer 2

If that computer gets its address via DHCP, check your router's web interface, it might say what IP addresses are given out by DHCP. Try these one after another.

If that comptuter has a static address, get a network sniffer, like Wireshark, it's free and works on Windows/Linux. Connect two computers with crossover cable. Any packet you see in the sniffer that has a source IP address different from your "good" computer's IP, will be the IP address of the other computer.

However: It seems you cannot be even sure that troubled computer boots properly. So if you don't see any network traffic, it probably means that computer didn't boot properly, so you need a display to troubleshoot that.

Answer 3

There should be a set number of possible ip addresses on your home network. Probably 254 possible addresses. Running a ping scan against these should result in your finding the system correctly.

I used to have a batch script that would do this for me mostly automatically using just the windows command line tools, but I can't recall what it was at the moment. Give me a bit.

Ah hah!

nslookup is probably the easiest one to use. Using a batch script with a FOR loop to scan each number from 1-254 and appending that to the rest of your home network IP address (192.168.1. and outputting the results to a text file, you'll end up with a list of each and every host on your network. Gimme a couple more mins and I'll see if I can remember the syntax for that script I used.

Eh. Not finding anything that'll make it easy enough.

For the time you could put into this I'd just go get Zenmap (http://nmap.org/zenmap/) and scan your local network subnet. I'll find the computers there and should make it pretty clear which one is the headless system.

Answer 4

Ping the broadcast address of your network then check your arp cache for it's mac address. The Mac address should be physically labeled on the board/card.

For example: 192.168.1.254 would be the broadcast on the 192.168.1.0/24 network. So if you have a subnet of 255.255.255.0 (which most home networks do) your broadcast is .254. So for my example ping 192.168.1.254 -t and let it run for a minute or two (it will say, "destination host unreachable" but it is working...). Then run the Command arp -a and you will get a list of active hosts on your network. Now check the list for the mac address of the network card on the missing pc and you have found your PC.