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[Ntp] Re: [EXT] Re: Re: [EXT] [EXT] Focussing loop detection on loop detection only.

Hal Murray <halmurray@sonic.net> Fri, 10 July 2026 07:51 UTC

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To: "Windl, Ulrich" <u.windl=40ukr.de@dmarc.ietf.org>
From: Hal Murray <halmurray@sonic.net>
In-Reply-To: Message from "Windl, Ulrich" <u.windl=40ukr.de@dmarc.ietf.org> of "Fri, 10 Jul 2026 06:54:12 -0000." <30f48c3d49604f93906484ae01796e3b@ukr.de>
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CC: Miroslav Lichvar <mlichvar=40redhat.com@dmarc.ietf.org>, David Venhoek <david@venhoek.nl>, NTP WG <ntp@ietf.org>, Hal Murray <halmurray@sonic.net>
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Subject: [Ntp] Re: [EXT] Re: Re: [EXT] [EXT] Focussing loop detection on loop detection only.
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Windl, Ulrich said:
> I think it would be an interesting experiment to disable loop detection
> in servers we have right now (NTPv4) and see what actually happens, i.e.:
> can someone force a sync-loop that persists for (say) more than three
> polling intervals? 

Server A points to an outside startum 1
Server A is stratum 2
Server A also points to server B as a backup.

Server B points to server A.
Server B is startum 3

Now, break Server A's connection to the outside world.
After a while, Server A will switch hto using Server B
Server A becomes startum 4
Server B becomes startum 5
Server A becomes stratum 6
Iterate until they fall off the edge of the world.


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