Re: [Ntp] Antw: [EXT] Re: CLOCK_TAI (was NTPv5: big picture)

Martin Burnicki <martin.burnicki@meinberg.de> Mon, 11 January 2021 09:47 UTC

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To: Hal Murray <hmurray@megapathdsl.net>
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From: Martin Burnicki <martin.burnicki@meinberg.de>
Organization: Meinberg Funkuhren GmbH & Co. KG, Bad Pyrmont, Germany
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Date: Mon, 11 Jan 2021 10:47:50 +0100
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Subject: Re: [Ntp] Antw: [EXT] Re: CLOCK_TAI (was NTPv5: big picture)
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Hal Murray wrote:
> 
> martin.burnicki=40meinberg.de@dmarc.ietf.org said:
>> Beside this, there are lots of potential problems due to different shapes and
>> intervals for the smearing.
> 
> Is that a real problem?  I thought that the big boys had agreed on linear over 
> 24 hours centered on the leap.

There are not only the big boys, and in the past some of them did it in
different ways.

For example, folks who have their own NTP servers for their internal
network but want the time of their local machines synchronized to cloud
machines provided by the big boys they have to carefully check if and
how the time from the different NTP servers is smeared.

In the past, some big boys have even changed what they think is the best
way of smearing, so if smearing went fine in a mixed environment during
one leapsecond, that doesn't necessarily mean everything will still be
fine when the next leap second occurs.

And unlike the folks on this mailing list, many admins aren't even aware
of the details they'd have to look at.


Martin
-- 
Martin Burnicki

Senior Software Engineer

MEINBERG Funkuhren GmbH & Co. KG
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