Take the 2-minute tour ×
Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

I have a single server that is also a domain controller in a cabinet, there are no other servers attached to its domain. I've reset the time in the BIOS (from what I recall) and in Windows to the current correct time, over a period of a few days the time will be off by about 20 minutes.

Since it's a DC it shouldn't be getting time over NTP, correct?

Does this mean the issue could be with the BIOS battery? The server is almost 4 years old and the CMOS battery is original.

share|improve this question

1 Answer 1

Since it's a DC it shouldn't be getting time over NTP, correct?

No. Not unless you configured it that way.

How would a domain controller automatically configure itself to use an external NTP source? That would be a really bad default behavior for many reasons.

The DC holding the PDC emulator role is used as the time source for all other DCs. Then, all clients sync their time from any DC, usually their logon server but not always. Since you are in a single-DC environment, you still need to configure the Domain Controller to sync from a reliable external time source. I suggest syncing from the ntp.org sources if you don't have another in mind.


Does this mean the issue could be with the BIOS battery? The server is almost 4 years old and the CMOS battery is original.

Probably not, but if you think that might be an issue, then replace it. They're only like $2.

share|improve this answer
1  
TL;DR: What Mark said. Or to put it the long way: Sync to an external, hopefully correct, time source is a different issue to time sync within the domain. It's much more important for the servers and workstations to have the same time in a kerberos based directory service like AD than it is for them to have the 'correct' time. This is why the former case is handled automatically, since its never the wrong thing to do, and the latter case is something the system admin has to sort out for themselves as they presumably know what their requirements and best resources for time sync are. –  RobM Dec 12 '11 at 21:04

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.