02-08-2011 07:06 PM - edited 03-16-2019 03:20 AM
Hey Everyone,
I am working with a client on an NTP syncing issue. While looking into it, I noticed that in the output of utils ntp status command, it shows that it is synchronized to local net at stratum 11.
The NTP setup on CUCM Pub is as follows:
Primary NTP: 172.30.1.1
Backup NTP: 172.30.1.2
See below (taken from CUCM Publisher):
admin:utils ntp status
ntpd (pid 5856) is running...
remote refid st t when poll reach delay offset jitter
==============================================================================
*127.127.1.0 LOCAL(0) 10 l 36 64 377 0.000 0.000 0.004
172.30.1.1 .LOCL. 1 u 61 64 377 0.325 -469.35 3.989
172.30.1.2 172.30.1.1 2 u 39 64 377 0.256 -480.96 5.440
synchronised to local net at stratum 11
time correct to within 12 ms
polling server every 64 s
Current time in UTC is : Wed Feb 9 02:51:56 UTC 2011
Current time in America/Toronto is : Tue Feb 8 21:51:56 EST 2011
Does anyone know what the literal meaning of synchronised to local net at stratum 11? Does it mean that CUCM Pub is defaulting to it's own local clock? Or that the NTP server itself is 11 strata away? I know that the CUCM will not sync with an NTP server that has a 10 or higher stratum.
And if it's true that the CUCM Publisher is not syncing with the NTP server, any ideas on how to fix this issue?
Thanks,
Neocec
Solved! Go to Solution.
02-09-2011 07:32 AM
That means CUCM cannot synchonize to any external NTP, thus default to the local clock.
Since the local clock is at stratum 10, CUCM will be stratum 11 if it synced to the clock.
Michael
02-08-2011 07:41 PM
Two questions:
1) What platform was the NTP server? Was it a Cisco router or a Windows server?
2) How long have you waited after configured the NTP server on CUCM?
Thanks!
Michael
02-09-2011 06:48 AM
Hey Michael,
1) The NTP server is a Windows Server
2) We restarted the service and it has been about 20 hours since doing so. I just ran the utils ntp status command again and it still showing stratum 11.
Thanks,
Neocec
02-09-2011 07:15 AM
Windows NTP server by default has dispersion of 1000 (ms), which is unacceptable from CUCM (and other Cisco UC appliances) perspective. You need to change that to 0 (and restart Windows Time Service).
See http://htluo.blogspot.com/2009/02/ntp-network-time-protocol.html for details.
Michael
02-09-2011 07:29 AM
Hey Michael,
Thanks for your reply. I am aware of that change in the registry that needs to be made (because I read your blog which is GREAT by the way . I have favourited it ).
But I just want some clarification on what synchronised to local net at stratum 11 means. What is the Local Net that it's being synchronized to? Is the local net the NTP server that has an 11 stratum? It's just a confusing line to me lol.
Thanks,
Neocec
02-09-2011 07:32 AM
That means CUCM cannot synchonize to any external NTP, thus default to the local clock.
Since the local clock is at stratum 10, CUCM will be stratum 11 if it synced to the clock.
Michael
02-09-2011 08:36 AM
Thanks Michael. I will try it and let you all know how it goes. I appreciate the replies
Neocec
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