[VoiceOps] [External] Re: [External] NTP Question

[Alex Balashov]

Interesting. I'm thinking there's something else off there. Perhaps the
hypervisor is incredibly oversubscribed?

On Mon, Feb 17, 2020 at 04:12:59PM -0600, Hunter Fuller wrote:

> I wouldn't say we need it to be "really precise," but we do need it
> within a couple of seconds, and on ESXi 6 we were seeing boxes as far
> as 500ms off. It may not apply to all VM environments, so I guess it
> could be worth testing. But it certainly scared me off. With physical
> NTP servers we achieve within 10ms generally.
> 
> On Mon, Feb 17, 2020 at 4:09 PM Alex Balashov <abalashov at evaristesys.com> wrote:
> >
> > On Mon, Feb 17, 2020 at 04:00:25PM -0600, Hunter Fuller wrote:
> >
> > > On Mon, Feb 17, 2020 at 3:57 PM Mike Hammett <voiceops at ics-il.net>
> > > wrote:
> > > > Is having four VMs running NTP a ridiculous proposition (well, other
> > > > than resources, which it'll consume very little)?
> > >
> > > Yes. NTP servers should never run in VMs.
> >
> > I don't know about that. The nature of virtualisation has changed
> > greatly over the past decade; VMs have gone from being a kludgy and slow
> > software-emulated environment to almost a first-class CPU guest, thanks
> > to paravirtualisation and supporting CPU features.
> >
> > And NTP is specifically designed for latency in a rather general sense.
> >
> > If you're using NTP for any really precise timing calibration, that's
> > the wrong vehicle, anyway.
> >
> > -- Alex
> >
> > --
> > Alex Balashov | Principal | Evariste Systems LLC
> >
> > Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free)
> > Web: http://www.evaristesys.com/, http://www.csrpswitch.com/
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-- 
Alex Balashov | Principal | Evariste Systems LLC

Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free)
Web: http://www.evaristesys.com/, http://www.csrpswitch.com/