[cisco-voip] 3rd-gen and newer IP phones 5-10 seconds slow

[Bill Simon]

Wait.  Hold up.  NTP servers are in our default options on the DHCP server.

Would it take NTP servers from the DHCP options?

I have never read that the phones do that.

I can try experimenting with the phones' scope in DHCP on Monday if this 
might be it.  Either removing the NTP options or pointing to CUCM...

Bill Simon wrote:
> I'm not aware of any method to direct a SCCP-firmware phone to an NTP 
> source.  I have seen the option in the XML config file for a SIP load.
> 
> So, no, not trying to circumvent CM as the time source.  I'll check out 
> the bug you noted.
> 
> Thanks
> Bill
> 
> Wes Sisk wrote:
>> We have had at least one report of this before.  That issue appears 
>> associated to CSCsd54013.  I don't necessarily agree with that.
>> My recollection (questionable?) of this issue is that when 3rd gen 
>> phone are provided NTP server they ignore time from CM.  If the phones 
>> cannot sync from NTP source for any reason then they drift.
>>
>> Are you attempting to provide NTP source to the phones via any means?
>>
>> /Wes
>>
>> On Friday, May 08, 2009 5:10:44 PM, Bill Simon <bills at psu.edu> wrote:
>>> Running CM 4.1.3 with NTP configured on all servers to sync to two 
>>> reliable NTP sources and peer with each other for verification.
>>>
>>> I run ntpq and check each server and all are synced up.
>>>
>>> My 7940s and 7960s are right on time.  But newer phones, 7961, 7965 
>>> and 7906 are anywhere from 5 to 10 seconds slow.
>>>
>>> I am aware that older phones used SCCP messages to sync time, and 
>>> newer phones appear to use a different method.  SIP firmware loads 
>>> use NTP; what do SCCP firmwares use?
>>>
>>> Even after a **#** reset, the phone's time is lagged.
>>>
>>> Is this a defect of the Java-based firmware, or do I have another 
>>> issue within the system causing the lag in the time displayed on the 
>>> newer phones?