8831 Keeps Unregistering

GEglPhoneman · ‎09-05-2017

Perhaps this is a rookie question, but since I'm pretty much a rookie when it comes to VOIP, I'll ask it. We have two newly installed 8831's that keep unregistering. The softkey Apps option then appears. If we do a factory reset it comes back fine, stays that way for perhaps several days or weeks, then randomly unregisters again. Any ideas what might cause this, or how to fix permanently? Only the two new ones have been doing this? These are the only 8831's at this location. The 7937 which was also new to the location has been fine. I've compared the firmware with that of all our other locations and it is the same. I've reached out to some of our senior engineers, but they seem to be busy. I'm hoping to get some feedback that perhaps I can point them in the right direction or fix myself. Thanks for any advice in advance.

P.S. - New to site and my first post here. If I have posted in the wrong location I apologize.

christoph.hable · ‎09-07-2017

Hi! Did you check the CiscoSyslogs in the Realtime Monitoring Tool (RTMT) what was the last OutOfServiceReason for these devices?

Do you know the firmware version of the 8831s at this location?

There is a known bug, maybe it happens also for short duration network hiccups (whatever the reason is). It is fixed for exmple in 10.3(1)SR3. If the phones have an old firmware (9.3.3) you need to upgrade first to an intermediate firmware (this is what most people forget and 8831 stay on the old release) - cmterm-8831-sip.9-3-3-TO-10-3-1-v2.cop.sgn

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cuipph/8831/firmware/10-3-1-sr3/cs38_b_rn-8831-8831nr-1031sr3.html

Below the bug description:

"CSCuh18303 - Phone can't register to cucm after unregister for long duration
Symptom:
8831 phone can't register to CUCM after it has been unregistered for a number of minutes.

Many possible reasons why the 8831 remained in an unregistered state to begin with. Examples:
- The CUCM server is shutdown
- Network between phone and CUCM is down
- Auto-registration disabled and phone device not configured on CCMAdmin"

PS: Just try the search option in the future, often there are other threads with same or similar problems. They also point you to the proper location e.g. IP Telephony"would be a good location for your question. In worst case it will be relocated from moderators.