Snom370 phone dropping off - unable to receive calls


We are having some issues with some extensions failing to receive incoming calls after what seems to be a random period of time.

We are using Snom370 phones and the phone itself says its registered OK with the PABX but in FreePBX it says

XXXX/XXXX (Unspecified) D Yes Yes A 0 UNKNOWN

The phone is able to make outbound calls but users receive ‘Service Unavailable’ when trying to make a call to this extension. The phone never loses its IP and you can always access the web interface ok.

If we jump on the phone and hit re-register it seems to fix the issue for a period of time before dropping off again.

This only seems to be happening on a small number, say 5-6 phones out of 100+ phones. The phones have all been provisioned the same and the extensions all created exactly the same.

Is anyone able to assist in where I start to resolve this issue. I’m happy to provide further information if required.

We are running FreePBX 2.11.0 22 and Asterisk 11.20.0, this is actually an Elastix box but their community forums seem pretty quiet so hoping you guys can help out.

Many Thanks in Advance


Asterisk 11.20 has a bug that does exactly what you are describing. 11.21 has the fix for that bug, however, you should probably just go straight to 11.22 since that is the current release of the 11.x branch.

Thanks for the reply Tom

What’s the safest way to update asterisk in an Elastix/FreePBX environment without breaking a bunch of stuff?

Can you safely run

yum upgrade asterisk11

On this PBX it’s purely SIP and an IAX trunk to another Elastix server.

Once again, thanks for the reply.

@wys_matt You’ll need to follow Elastix’s suggested method of upgrading Asterisk. I have no idea how they manage their upgrades for things like this.