Re: [Ntp] Is one refid enough

Heiko Gerstung <heiko.gerstung@meinberg.de> Thu, 05 September 2019 11:07 UTC

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Date: Thu, 5 Sep 2019 13:07:53 +0200
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Thread-Topic: [Ntp] Is one refid enough
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From: Heiko Gerstung <heiko.gerstung@meinberg.de>
To: Miroslav Lichvar <mlichvar@redhat.com>, "ntp@ietf.org" <ntp@ietf.org>
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Subject: Re: [Ntp] Is one refid enough
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> On 05.09.19, 13:04 "ntp im Auftrag von Miroslav Lichvar" <ntp-bounces@ietf.org
>> if A Is stratum 1 and A->B->C->D then B would never choose D
>> because it is stratum 4 and B itself is stratum 2. 
> 
> That's how it worked in NTPv3 and it limited the selection
> significantly. In NTPv4 clients are allowed to synchronize to
> sources
> having the same or higher stratum. It has some weight in the
> source selection (it is included in the root distance), but it
> doesn't
> prevent the selection.

Thanks for the clarification, in this case the chain of InstanceIDs would also be useful to prevent loops like A-B-C-D-B ..

Best Regards, 
    Heiko



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