Periodically phones lose registration

[netelligence]

Greetings,

We have a number of clients that we cloud host. Periodically random phones lose their registration. Clients will call us saying that whatever phone isn't working. We tell them to reboot the phone and then it registers and we'll have to repeat the process. We've tried to educate the client that if a phone stops working to restart it first. Depending on the client, that works OK. However, we use Yealink T-41 and T-46 phones and sometimes the client will hold the wrong key down to reboot the phone and they end up factory resetting it ... which causes a whole new problem.

Anyway, I don't think telling clients that they have to reboot their phone every time it stops working is a good solution. Most of our clients come from a traditional PBX environment where the system "just works".

We have clients that are remote extensions only and we have clients that use SBC's. Both types have the problem. I haven't noticed that one is better than the other. This has been happening to us from the beginning of our hosting business -- v11, v12, v14, v15.

Why does this happen and how can we prevent it? Why does the phone quit trying to register until it is restarted?

Thanks for any insight.

Netelligence

 

[jholcombe]

It's a Yealink firmware bug. If the phone loses connection to the 3CX phone system (for example, if a bridge or switch between the phones and 3CX server are rebooted), then the phones will need to be re-registered. I've had this problem ever since upgrading my Yealink phone firmware to 28.80.0.110, although I think the problem also existed with a previous firmware. I know my phones on 28.80.0.60 don't have the problem.

If a newer firmware correct the problem, then I wish that 3CX would support the newer firmware on V14. Currently 28.80.0.110 is the newest firmware supported by 3CX for the Yealink phones on V14. I asked 3CX support about it and the rep suggested that I upgrade to V15. The problem with all of these upgrades is they always introduce problems or unwelcome changes. This problem, for example, is significant enough that I'm really surprised they're not doing anything to address it.

The older Nortel system that the 3CX replaced did not have this problem. It's really frustrating because from the perspective of the end user and their supervisors, this "newer system" (3CX) should perform better than the older system (Nortel). However in this particular area that is not the case. The "never had to reboot their Nortel phones". Yealink and 3CX both need to get together, fix the problem, and release whatever updates are necessary to correct the problem. Maybe it could be fixed with a template update? I don't know, but they need to fix it!

 

[netelligence]

Thanks for your input. I'll try to pay more attention to the firmware versions and see if I notice a pattern there. FYI, I have some v15 and the problem still exists with Yealink 28.80.0.130.

Others seeing the same things? Other insights?

 

[JST]

Sadly, we see the same problem with other phones (Cisco, Gigaset, Yealink T2x) as well. We are using managed switches and I don't see any evidence that the connected switch has rebooted if the problem occurs. Furthermore, the extension continues to show as registered for us. It just can't make calls until the next renewal occurs. One observation I made is that it normally happens after making (or receiving) a call.

Not sure if that is really a firmware problem...

I am guessing that a register should always take place when a call has completed. I am also guessing that this register should reset the registration period. Is it possible that the 3CX system occasionally forgets to reset the registration time for an extension? If that happens, the phone would assume that it has a full 30 minutes, but 3CX is still counting down from the value prior to the call?

I am not an expert when it comes to voice connectivity, but I did notice that the problem is happening less often when we reduce the registration period... Hence my theory above. Maybe somebody is more technical in this area?

 

[jholcombe]

My problem is not the phones completely losing registration, but the BLF lights stop working. The phone still works except for the lights. Maybe it's something that could be corrected with some template modification (not a firmware issue). I would certainly appreciate any help in getting this resolved. It has been a problem now for several months. The BLF keys are fine until the phone loses connection with the server. When that happens, the BLF lights don't work again until the phone is rebooted. If the server is rebooted, all phones have to be rebooted before the BLF lights will work again.

 

[JST]

Yes, your problem is totally different, but netelligence is talking about phones losing their registration which seems to similar to my problem. So, I have shared my findings in hope that we can find some similarities.

In your case, it seems odd that even rebooting the server doesn't correct the issue. In my experience, that normally points at an issue with the phone, but I guess it could also be that something in 3CX doesn't get refreshed with a reboot.

 

[nb]

But this is an old yealink bug..
Make sure you upgrade to the latest supported firmware.
And make sure the connection between the phones and the VPS is stable.
You can switch from UDP to TCP in the phone to gain more persistence.

Loosing BLF in this scenario (if your pbx is on the cloud) rest assured that sip notify packets are going elsewhere.. Check the network. Use SBC.

 

[jholcombe]

Loosing BLF in this scenario (if your pbx is on the cloud) rest assured that sip notify packets are going elsewhere.. Check the network. Use SBC.

My phones are on the same LAN as the 3CX server. The problem (with BLF) for me only occurs when the connection between the phone and server is broken, but the phone remains powered. It can also happen if the server is rebooted (and the phones remain powered). The phones will re-register, but BLF doesn't work anymore. All Yealink phones need rebooted or their BLF lights won't work anymore.

 

[604]

Just bumping this to add that I also experience this problem.
I have a hosted VPS running latest Linux v15 SP5, and Yealink T29G running 46.81.0.60 firmware.
When the server is rebooted, the phone loses registration with 3CX, although the phone still thinks it's OK. Incoming calls don't work, but outgoing does. Only after rebooting the phone does it correctly re-register with 3CX and work normally again.

Does anyone know if there is a way to send a reboot command to phones remotely, without customer interaction?

 

[JasonNadeau]

From my experience this is usually fixed by bringing down all the timers.
In the yealink phones, set the server expires to 120, and sip registration retry timer to 10.
... Whats it set at now ?

 

[604]

Expire is at 120 by default. The retry timer is set to 30, so I'll drop it to 10.

 

[JasonNadeau]

bring the expire down to 60 ... I've had to do that at some clients who's remote phones would also de-register

 

[604]

OK, I have it set to 60 / 10.
I rebooted the server again to test, and the phone did appear to re-register. I will keep an eye on it on future restarts. Thanks for the tip!