cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
10698
Views
0
Helpful
6
Replies

NTP issue: synchronised to local net at stratum 11

Giovanni Ceci
Level 1
Level 1

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

1 Accepted Solution

Accepted Solutions

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

View solution in original post

6 Replies 6

htluo
Level 9
Level 9

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

http://htluo.blogspot.com

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

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

http://htluo.blogspot.com

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

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

Thanks Michael. I will try it and let you all know how it goes. I appreciate the replies

Neocec

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: