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Which DNS server are my clients resolving against ?

Config - 5 DC's all DNS & GC's.  3 are w2k 2 are w2k3.  Clients mainly XP some w2k, approx 2500 nodes

Is it possible to identify which DNS server my clients are resolving against?  Like in WINS having the owner.  I ask because I want to remove 2 of the W2k DC's which are currently set to primary & secondary DNS on nodes that have DHCP configured, so this process is straight forward.  But I know that there will be nodes out there that have not been made DHCP so I need to get an idea of what clients are resolving where before I start.
3 Solutions
Hi the one which is set as the primary DNS is always the once resolving and registring for clients. go to the command prompt and then type nslookup and then may be you type any pc name see which is the ip resolving then that is the one which is resolving.  if not you can go to command prompt and then type ipconfig /all to see the primary dns. if not you can also go to your DHCP and check which is the primary and secondary set for the user.

Hope this helps
Your DHCP clients ar easy just do what Kamal suggests because DHCP clients always get the primary & secondary DNS server with the DHCP scoope. But if you have clients that have fixed IP and DNS hardcoded then you might need to go to them and see which DNS server they are resolving to.

You should be able to find your fixed IP clients by comparing the DHCP lease with the scoope.
cochAuthor Commented:
ormerodrutter - Can you explain how I would compare the DHCP lease with the scope please
Jeremy WeisingerSenior Network Consultant / EngineerCommented:
If you have lots of clients and you don't know which ones are DHCP and which are static then you could capture the DNS traffic on the DCs you want to decommission and see what clients are using them.

Filter everything but port 53.

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