[ntp:questions] ntpd stays synced after loosing gps

Nickolay Orekhov nowhere at mail.ru
Thu May 12 07:13:31 UTC 2011


Thanks, Dave. That's exactly what I didn't understand.
Will the server without sync lower it's stratum somewhen? According to tos
maxdist maybe?

Let me explain. I need to set some criteria of local clock "goodness".
Goodness for me means low root dispersion and exact time.
And I need to set this criteria simultaneously on proxy and on clients. For
now I used "sync_unspec" in ntpd status, but proxy sets "sync_unspec"
immediately after loosing GPS
and clients set it according to big root dispersion of proxy after some
hours maybe.

What system variable can I use? I think that good OS clock = (stratum < 16)
&& ( rootdisp < MAX_DISP ) && ( offset < MAX_OFFSET )
In this case server with no sync will be bad in any case,  server which was
synced will become bad after some time, server which has big offset will be
marked bad too.
Stratum needs to be checked cause just started server have offset and
rootdisp = 0
Am I right?

2011/5/11 Dave Hart <davehart at gmail.com>

> On Wed, May 11, 2011 at 15:29 UTC, Nickolay Orekhov <nowhere at mail.ru>
> wrote:
> > Other devices should also have status "unsync" and stop syncing but they
> > will continue to sync from unsynced source with stratum 1 infinitely.
>
> No, they will reject the source once its root dispersion ("rootdisp="
> in ntpq rv) exceeds the client's "tos maxdist" threshold (in seconds,
> default 1.5 in ntp-dev).
>



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