2 Domain controllers lose communication with each other

[gnarled]

I have 3 W2K DCs on my network. All are on the same domain in the same site.
DC3 can communicate (access folders, replicate, etc.) with DC1 and DC2 and both DC1 and DC2 can communicate with DC3

DC1 cannot communicate with DC2 and vice versa. DC1 can ping DC2 using name and vice versa (DNS is working). If I try to access a folder share from 1 to 2 or 2 to 1 it displays: The network path cannot be found. If I try to replicate between servers either way it does not work ether.
When I reboot the DC1 then everything works fine for a few hours then fails. It fails at any time and does not appear to be something that runs at a specific time that causes the problem.

If anyone has heard of something like this before or has any ideas or needs more information to help please let me know. I have search the Internet for days and have not seen anything like this.

 

[kmkeshav]

Did you run dcdiag on these two problem servers and found any errors?

Looking up the events in the event log also helps.

 

[dberg35]

I had a similar issue a few months ago and it turned out to be a thing called "Tombstone End Of Life". Check this out and also try Googling it.

http://technet2.microsoft.com/Windo...25d6-417c-9d8b-6e22f472ef3c1033.mspx?mfr=true

 

[gnarled]

I have run netdiag and dcdiag and errors do come up but it seems the errors are the result of the two domain controllers not being able to communicate not the cause. If I run the tests after rebooting when they are both communicating there are no errors.
Also, I have looked up all the errors in the event log and the same thing. They seem to be the result of the problem not the cause.
DC1 is an Exchange Server and I have considered demoting it to a member server, but I am not sure the problems that may occur from that.
Also running netdiag while both computers are communicating does not reveal errors, but when they are not communicating I get:
DC list test . . . . . . . . . . . : Failed
Failed to enumerate DCs by using the browser. [ERROR_NO_BROWSER_SERVERS_FOUND]

Trust relationship test. . . . . . : Failed
[FATAL] Secure channel to domain 'DYNETEK' is broken. [ERROR_NO_LOGON_SERVERS]

Once again I think these are the result and not the cause, but I am not sure. Thanks for helping out guys.