Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

How do I find which computer is using a particular private IP address? For instance, when I ping, I get a message "Reply from bytes=32 time =1 ms TTL=32". I don't know which computer has this IP address. I looked at 'Address Leases' and 'Reservations' in DHCP of our Windows Server 2003 machine, but it does not include this IP address. Is there some other way of determining which computer is using this IP address? Thanks, in advance, for your help! - Charles

share|improve this question
Thanks so much, TrueDuality and AliGibbs! It worked. Using your method, I found out that it belonged to our Panasonic phone system. – Charles Jan 20 '11 at 16:28
up vote 5 down vote accepted

I can help you narrow it down, but unless you are using a managed switch it's the best you're going to do. By the sound of it you're using Windows so I'll give you instructions for that

1) Open a command prompt on a machine on the same subnet (this is important, this won't work from a different subnet)

2) Ping the address and make sure you get a response

3) Type "arp -a" and find the reported "Physical Address" for that IP

4) Lookup the first 6 hex digits here

You can use that manufacturer to take an educated guess what the device is.

share|improve this answer

You can try ping -a, this should attempt to resolve the host for you (in a windows environment)

share|improve this answer

Also, if the target is a windows (or runs samba shares), you can use

net view \\IPaddress

to gather more clues :-)

share|improve this answer

nslookup <domain-name> could give you the hostname of it, which may help.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.