CME – Sip Endpoints / SKINNY Endpoint and Router and the headache of Synchronizing Clocks

First let my start off by saying this is something that if you have never run into doesn’t seem to be a daunting task and once you understand all the different components it isn’t.  But getting from point A to B is not always ice cream and xbox.   To properly trouble shoot the problem me must first understand the basics of where the time is pulled from each one of the devices.

Router – Local and or NTP server

Sip Endpoint – NTP server

SKINNY Endpoint – CME

Remembering these simple things and you can alleviate a lot of stress later on when one set of devices are off by an hour.   And when you start to take into account daylight savings time (DST) requirements it throws another clown into the party.    Here are the individual configurations needed for each of the device types for congruent clocks.

Router 

-          Local –  #ntp master

-          NTP server - #ntp server  X.X.X.X

-          Clock  time zone - #clock timezone  GMT +23/-23

-          DST – clock summer-time DST recurring

Skinny Endpoints in Telephony-services

-          Time –zone  - time-zone ( * make sure you are 100% on the DST of the location you are specifying as this can cause headaches)

SIP Endpoints in Voice Register Global

-          Time-zone – timezone (*make sure you are 100% on the DST of the location you are specifying as this can cause headaches )

-          Ntp-server – ntp-server X.X.X.X (Usually the same NTP server that the router is using.  I have had problems with using the NTP master and sourcing the local CME box.)

Simple Right?  Well it is now, good luck and have fun studying.