I am having an occasional problem with my main domain controller. As far as domain controllers go, we have 3 servers in the picture:
Primary DC, GC, DNS server, running 2008 (the one having problems).
Backup DC, GC, DNS server, running 2008. Also has other file server roles.
Exchange 2007 server, running 2008.
This seems to happen about once every couple weeks. Right now, I am having the problem. My primary DC starts acting weird. I can't access AD users and computers, I can't import users into Exchange, but I do have access to AD users and computers through RSAT. When I have this problem, rebooting the server usually fixes the problem, but only for a couple weeks.
While trying to access Active Directory users and computers from the DC, I get this error message:
"Naming information cannot be located for the following reason: The server is not operational.
If you are trying to connect to a Domain Controller running Windows 2000, verify that Windows 2000 Server SP3 or later is installed on the DC, or use the Windows 2000 administration tools. For more information about connecting to DCs running Windows 2000, see Help and Support."
In my system event log, I have a lot of these events:
1054 - "The processing of Group Policy failed. Windows could not obtain the name of a domain controller. This could be caused by a name resolution failure. Verify your Domain Name Sysytem (DNS) is configured and working correctly."
We used to have a 2000 DC in the picture, but it had SP4 on it from the get go. And it has been completely removed from the schema for months. Does anyone have any ideas what the issue could be? This also happens to our other 2008 domain controller on a regular basis. It seems like it's one DC on one week. And rebooting the problem server temporarily fixes the issue.
When one server is like this, here are the things that don't really work:
You cannot add a computer to the domain
You cannot create a new user on that DC
You cannot import an AD user into a new exchange mailbox
A user cannot change their own password. It must be set by me, manually on RSAT, once on each DC
Any help from you Microsoft gurus would be greatly appreciated.