Re: NTP - orphan mode with SAME stratum ("tos orphan 6") FAIL to sync.

On 2009-04-06, Unruh <unruh-spam@xxxxxxxxxxxxxx> wrote:

Steve Kostecke <kostecke@xxxxxxx> writes:

On 2009-04-06, Unruh <unruh-spam@xxxxxxxxxxxxxx> wrote:

ntp can take 10 hours or more to sync.

I believe you mean "ntp can take 10 hours or more to amortize a
clock's offset within the limits of the hardware."

Yes, that is what I meant.

Please stop spreading FUD, then.

"Sync" is usually defined as "calculating the offset between a clock
and a reference standard, stepping or initiating a slew to correct the
offset, and becoming ready to serve time to others". ntpd is capable
of "syncing" in under 10 minutes. Even less if the initial offset is
less than 128ms and/or 'iburst' is used on the server lines.

If serving a time that ntp knows to be wrong by say 120ms is OK, then
yes, I agree that ntp can sync in much less time.

ntpd is able to serve time when it is synced to a time source. There is
no "maximum allowed offset" setting.

It is imcumbent on the operator of an ntpd (or some "ntp client") to
use enough time sources so that an outlier that is off by 120ms will be
detected and voted out.

--
Steve Kostecke <kostecke@xxxxxxx>
NTP Public Services Project - http://support.ntp.org/
.

Relevant Pages

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