Configuring Time synchronization on your servers is pretty easy. There are articles like this one that walk you through it like this one:
and this one for syncing clients on a domain to a DC:
But what if your DC's are virtual machines? Mine are. And yep, I ran into issues.
I could configure them until the cows came home, but my time on the PDCe would not change (and was off by about 20 minutes....VERY annoying!)
To fix, I had to set the HOST machine (a member of my domain) to synchronize to an external time source. (For me, here in Seattle the time source I use is: bigben.cac.washington.edu (CNAME ntp-uw.usno.navy.mil)
Then turned off the windows time source on the PDCe, and set hyperv integration on this VM to use the Integration time sync.
I ran the command: w32tm /resync and WHAMMO, all my clocks updated. immediately.
And stayed that way.
A friend of mine said he did the flip flop of this: he turned off the HyperV Time Synchonization service (under Integration services) and that worked for him.