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Date: Fri, 29 Nov 2013 18:43:32 +0100
From: =?ISO-8859-1?Q?Roger_Pau_Monn=E9?= <roger.pau@citrix.com>
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To: Karl Pielorz <kpielorz_lst@tdx.co.uk>, <freebsd-xen@freebsd.org>
Subject: Re: Xen Guests / NTP best practice?
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On 29/11/13 16:23, Karl Pielorz wrote:
> 
> 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?

There have been some improvements in 10 regarding timekeeping, now
FreeBSD makes use of the PV timer and PV clock when running under HVM,
which should be more stable.

Could you try if your issues with ntp are reproducible on 10?

Roger.