How to find out which domain controller i'm talking to?

To find out which domain controller your PC is talking to, use the following command:

nltest /dsgetdc:domainname.local



This is very handy when testing your active directory sites and services topology to ensure it is setup correctly. If you want to understand the process in which a client computer locates its domain controller please see this post:

http://clintboessen.blogspot.com/2010/05/how-clients-locate-domain-controllers.html