Xen Guests / NTP best practice?

[Karl Pielorz]

Hi,

We have a number of FreeBSD 9.x boxes now running under XenServer 6.2

Does anyone have any info / best practice / guides for what's best to use 
NTP / time sync wise?

I've noticed that NTP isn't "overly happy" on some of these hosts (i.e. it 
doesn't seem to settle on some, or will run for a while - then de-sync).

We have two local NTP servers (not virtualized) - should we be getting the 
guest to sync? - Can Xen keep the clock in sync for us (Xen itself is 
pointed at the two ntp servers) - or are there any options / configs we 
should consider using with NTP to keep time sync'd up?

Thanks,

-Karl