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I am trying to setup an active directory trust between two domains. When I set up the trust from my domain it does not work.

All my servers are Server 2008 R2 with the domain functional level of 2008 R2.

Here are my steps:

  1. start, administrative tools, active directory domains and trusts

  2. Right click my domain and then properties

  3. Click the trusts tab and then "New trust"

  4. I type the name of the other domain and click next

  5. Next it tells me "the name you specified is not a valid Windows domain name. Is the name a Kerberos V5 Realm and asks if it is a Realm trust or Trust with Windows domain.

Does anyone know whats going on? I have been googling all day and cant find the answer. Any help much appreciated.

share|improve this question
I've edited your question to be a little more sane. You don't make a trust between domain controllers, you make a trust between domains or forests. There is also no such thing as a "main" domain controller, they are multi-master peers. The PDC Emulator has a special role in external trusts, but that doesn't appear to matter much here. You also said that you have all 2008 servers with a DFL of 2008 R2 which is impossible. I assume you mean that your servers are all 2008 R2, so I've edited your question appropriately. – MDMarra Oct 2 '13 at 19:55
Also, you don't mention what kind of trust you are trying to make here. Is it a forest trust? An external trust? What is the DFL of the trusted domain? Are you trying to create the trust inbound or outbound or two-way? – MDMarra Oct 2 '13 at 19:58
Forest trust. I am trying to do a two way trust. – Mike K Oct 2 '13 at 20:09
up vote 4 down vote accepted

You need to be able to resolve the FQDN of the active directory that you wish to trust and also one or more domain controllers in that environment as well. This is typically done with either a DNS conditional forwarder that points to one or more of their DCs, or a stub zone.

If you do not have working name resolution between the two environments, you cannot create a trust.

share|improve this answer
MD, thank you very much. I will give this a try right now and report back. – Mike K Oct 2 '13 at 20:05
It works, I really appreciate the help! – Mike K Oct 2 '13 at 20:08

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