In struggling with time synchronization under Windows 2008 R2, I came across an issue that had me stumped for a bit. I have a client with Windows 2008 R2 Standard running in a virtual machine in Hyper-v. I have configured it to sync time from pool.ntp.org using the w32tm as instructed here, here and here.
The Hyper-v host is getting it’s time reference from the PDC that it is hosting as well. When the client complained that the time was off by something like 8 minutes, I began checking into the issue. When running
w32tm /stripchart /computer: target /samples: n /dataonly
I was getting back sporadic 0x800705b4 errors mixed in with the reports that my server was 378.023845629 (or so) seconds off. I didn’t see reference to that anywhere I Googled. for it to error every time? Sure. Mixed in the same results with successful connections? Not one. I checked the firewall settings anyway. Also, forcing sync had no effect. The clock was still off by three hundred and seventy whatever seconds.
Finally I found my problem. In integration services, time sync to the host is one of the options. So I was syncing my host to my PCD which was trying to sync pool.ntp.org, but being overridden by the integration services and syncing to the host.
Moral? Virtual machine settings –> Management –> Integration Services –> Time Synchronization? Uncheck it.