Yealink phones don't come back after internet outage

[Peter Richardson]

Hi all,

Have been using 3CX and Yealink phones for about 3-4 years now. I've found a strange thing where if the internet goes down, sometimes the phones don't come back up and require a manual reboot, which involves logging into every 3CX cloud hosted box, checking which clients have phones that are down, calling them and stepping them through the process of unplugging and replugging every phone or the appropriate PoE switch. Strangely, it doesn't happen to every yealink phone (we use T41S, T21P E2, T48S and W60 accross all sites). I remember having found something in the web interface before about the maximum times it tries to connect to the SIP server before giving up forever, so I had a look in the template and it might be this line:

account.1.sip_server.1.retry_counts = 3

1. is this line in the template the culprit?
2. if so, why didn't all phones drop out?
3. why would there be a max limit on how many times the phone tries to connect? Because if it's retrying once every minute or two, that would mean an internet outage of 5-10 minutes would be enough to bring them all down indefinitely...until the IT guy (me) gets time to contact every client
4. could it be something more sinister that I'm missing here?

Any help, ideas, suggestions are much appreciated! Thanks guys!!

 

[nub]

any other ideas, anyone?

The phones are have static ips, so the watch dog never triggers to reboot as the config never changes http://support.yealink.com/faq/faqInfo?id=76 maybe try one of them with dhcp option 66?

are you using RPS? if not try one of them with it and see if the watchdog catches it.

 

[Peter Richardson]

Thanks @3cxnub yes we are already using DHCP Option 66 - AKA - TFTP server.

I'm not sure how that article relates to the issue of the phones not registering after the internet goes down for some period of time. It's not that the phones are restarting, it's that they stop trying to register.

 

[nub]

Thanks @3cxnub yes we are already using DHCP Option 66 - AKA - TFTP server.

I'm not sure how that article relates to the issue of the phones not registering after the internet goes down for some period of time. It's not that the phones are restarting, it's that they stop trying to register.

That was my point, rebooting is what you want them to do and the watchdog will reboot for almost any IP reason but not sip. Which is what you need.

 

[Peter Richardson]

Oh I see. Yes absolutely!