Re: [Ntp] NTPv5 and anycasting

Kurt Roeckx <kurt@roeckx.be> Thu, 03 December 2020 22:42 UTC

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Date: Thu, 03 Dec 2020 23:42:16 +0100
From: Kurt Roeckx <kurt@roeckx.be>
To: Philip Prindeville <philipp@redfish-solutions.com>
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Subject: Re: [Ntp] NTPv5 and anycasting
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On Tue, Dec 01, 2020 at 10:41:01PM -0700, Philip Prindeville wrote:
> Sorry if this has been discussed already, but do we want to have a specific prohibition against the use of anycasting with NTPv5?
> 
> I can’t see the point in sending packets non-deterministically to one of possibly many servers with different clock values, RTT’s, etc.

I don't see how anycast changes anything at all. It's true that
because of routing changes that the RTT might change, but
that's not different then any other route change. The only thing
that's really different is that because of routing changes you
might actually talk to a different server, but without anycast
you can also talk to a different server each time because there is
a load balancer in between. And NTP should deal with all those
without any problem.


Kurt