Solved Phone in Ring Group Suddenly Not Ringing

[RHopkinson]

Yesterday (Tuesday, 6/22), a client called and advised that one of the 10 Snom D717 phones in their ring group is suddenly not ringing. Calls placed from one extension to this one ring busy, and a test rule I created to route my external call directly to the extension (bypassing all other programming) rings directly to the extension's voicemail. I toggled the extension's DND and they confirmed that the phone indicated that it went from Available to DND and then back to Available. I verified that the phone was on the latest version of the firmware, and even had them factory reset the phone, but after assigning it back to the extension, the issue persists. All other functionality is working on this phone (they can make calls and pick up calls in the shared parking orbits).

They are running 3CX Professional 16.0.8.9

I checked the extension's settings in the Forwarding Rules tab:

• "If I do not answer calls within:" is set to 20 seconds
• "Accept calls from Ring Groups" is checked
• "Accept Push Notifications" is checked

In the Options tab:

• "Disallow use of extension outside the LAN" is not checked (they have a SBC on site).

Any idea what could be causing this issue?

Thanks, in advance,
Russ

 

[VoIPTools]

It would be interesting to see if deleting the extension and recreating it would fix the problem. That is a pretty brute-force approach that requires the reprovisioning of the phone, sending welcome emails, handling prompts, recordings, and voicemails, but I have seen issues like this before where only recreating the extension fixed the problem. If the phone can accept an extension to extension call, it should be able to take ring group calls. I can not think of any user-defined restrictions that would only block these types of calls.

 

[ChrisC_3CX]

@RHopkinson
What VoipTools mentioned doing might save you some time if the issue is related to the extension's configuration as deleting and recreating the extension will essentially bring all settings for that extension back to default which means that direct calls to this extension should just work provided the IP Phone is registered. Factory resetting the IP Phone and reprovisioning it after re-creating the extension wont be necessary as it will still be able to use the same provisioning link it already has to reprovision. All you need to do is make sure that you re-add the IP Phone on the new extension manually by adding the model and MAC address in the "Phone Provisioning" tab. You will have to also keep the same provisioning method (STUN, SBC, etc), then, just reboot the phone and it should pickup the new settings.

Even if deleting and recreating the extension fails you'll at least be able to eliminate the possibility of this being an extension configuration issue in which case, you might need to check the IP Phone.

Before doing any of the above do bear in mind that a simpler way to check it would be to just access the 3CX Webclient for that extension, if not even the webclient receives the call, that would be proof towards this possibly being an extension configuration issue.

 

[RHopkinson]

The 3CX Webclient did not show an incoming call to the extension. I deleted the extension (after downloading its greeting and voicemail messages), and re-created it. After associating the phone with the newly-created extension, I was able to place several test calls to the extension with no issues.

I'd love to know why this happened in the first place, though. I have a backup of the 3CX config prior to deleting the extension. Is there any way to diagnose the problem with that info?

 

[leejor]

What I would have done is to check the 3CX Activity Log after I tried placing a call directly to the extension, and tried a call to the ring group. There may have been a clue, as to why the set was not accepting the call. Other than re-applying the backup, and testing again, in the expectation it will fail, I'm not certain you can ascertain what the issue was simply by something retained in the backup itself. It may have not been a setting causing the issue, but a software, or status anomaly.

 

[ChrisC_3CX]

@RHopkinson

Glad to hear you were able to resolve the issue!

Going through the backup files to determine what the issue was would most definitely be time consuming and might not even give you an answer unless it's an obvious configuration issue. I think what leejor mentioned would be the way to do it if you really want to identify the cause of the issue, though since you've already resolved it I do not think restoring the backup just to investigate this would be worth it.