[ntp:questions] NTP behaviour when server is not synchronized

Harlan Stenn stenn at ntp.isc.org
Fri Jun 29 18:07:26 UTC 2007

>>> In article <1183138077.657644.124300 at n2g2000hse.googlegroups.com>, Geir G <geir.guldstein at start.no> writes:

Geir> Hello, NTP configuration:

Geir> Client: ntpd version 4.2.2 at 1.1532 running on Windows XP Servers: 2
Geir> identical stratum 1 servers with GPS antennas directly connected

Are these 2 servers peering with each other?  They should be.

Geir> I want comments on the following observations. Unfortunately, the
Geir> system is currently not available, hence I cannot supply ntpq
Geir> diagnostics. I know that 2 servers is the worst possible
Geir> configuration, it is not necessary to comment that.

Geir> For some reason one NTP server lost its GPS synch. It switched to
Geir> internal clock started reporting stratum 12 when this happened. The
Geir> other server was perfectly synchronized and reported stratum 1.
Geir> Problem: ntpd rejects both servers and considers itself not
Geir> synchronized.

This tells me it was not peering with the other S1 server.  If it was, it
would report S2 and follow the time of the other S1 server.

Geir> Questions:

Geir> 1. Does the NTP server behave correctly when changing its stratum to
Geir> 12? Should it perform different/other actions when it considers itself
Geir> not synchronized?

If it is reporting S12 then you must have it configured to use its local
clock as a refclock.  ntpd is correctly reporting that it is sync'd to its
local refclock.

ntpd is behaving as designed.  It may be that your configuration is

Geir> 2. Does ntpd behave correctly? Is a server's stratum used in any way
Geir> in ntpd's clock selection process?


Have you visited http://support.ntp.org/Support/ConfiguringNTP ?


More information about the questions mailing list