[ntp:questions] NTP.log interpretation

Steve Kostecke kostecke at ntp.org
Sat Apr 19 14:50:37 UTC 2014


On 2014-04-19, Jason Rabel <jason at extremeoverclocking.com> wrote:

> Then I have three Stratum-2 servers that use the "server" line for
> the S1 servers, but in addition they use the "peer" line with each
> other S2 server. When you combine that with "orphan" mode if all my S1
> servers went down, the S2's would work with each other to figure out
> their best guess at the right time.

Orphan Mode is an automatic server discovery scheme. Nothing more.

Orphan Mode does not make it possible for the members of a "time island"
to determine the correct time in the absence of reference sources.

http://doc.ntp.org/4.2.6p5/assoc.html#orphan

Symmetric Active/Passive Mode (aka Peer Associations) allows the
creation of a bidirectional link between two ntpd instances.

http://doc.ntp.org/4.2.6p5/assoc.html#symact

In my experience, the ntpds in a peer association will ignore each other
when they have the same sys_peer (i.e. when they are "synchronised" to
the same source).

And the Mitigation Rules do not provide special Peer Classification for
Symmetric Active/Passive Mode.

http://doc.ntp.org/4.2.6p5/prefer.html#peer
or http://doc.ntp.org/dev/prefer.html#peer

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



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