Solved Duplicate, no working Yealink T46S

[FredyWenger]

Hi

I have a very strange problem since today
We use 3cx (hosted at a cloud provider).
We have some phones (including Yealink T46s) in the company (over a SBC) -> no problems.
Further we use one Yealink T46s and one Gigaset N510 IP pro (Dect - mobile) in a home office (direct access, without SBC)
3CX: Version 18.0 (Build 461)
Yealink SIP-T46S, FW: 66.86.0.5

Problem:
Since today, the Yealink T46S at the home office is showed duplicated with the same mac address in the 3cx console and don’t work (“no service”)
Note: The 3cx (Android) App and the Gigaset work without problems to that extension.
Reboot don’t solve the problem
We have deactivated the phone (disabled from power and LAN connection) since over a hour now.
One of devices has disappeared, the “second” phone still is showed in the console.
In my understanding, also the second phone has to disappear on the 3cx console, if it is offline more than a full hour..?

I have not found a way to delete the (second) phone on the 3cx (so that it can register newly)
We never had such a problem…
Is there a way to delete the second phone and what can this be…?

Thanks

 

[Rhys Haskell]

Hi

I have a very strange problem since today
We use 3cx (hosted at a cloud provider).
We have some phones (including Yealink T46s) in the company (over a SBC) -> no problems.
Further we use one Yealink T46s and one Gigaset N510 IP pro (Dect - mobile) in a home office (direct access, without SBC)
3CX: Version 18.0 (Build 461)
Yealink SIP-T46S, FW: 66.86.0.5

Problem:
Since today, the Yealink T46S at the home office is showed duplicated with the same mac address in the 3cx console and don’t work (“no service”)
Note: The 3cx (Android) App and the Gigaset work without problems to that extension.
Reboot don’t solve the problem
We have deactivated the phone (disabled from power and LAN connection) since over a hour now.
One of devices has disappeared, the “second” phone still is showed in the console.
In my understanding, also the second phone has to disappear on the 3cx console, if it is offline more than a full hour..?

I have not found a way to delete the (second) phone on the 3cx (so that it can register newly)
We never had such a problem…
Is there a way to delete the second phone and what can this be…?

Thanks

Is SIP ALG enabled on the end users home router?

 

[FredyWenger]

First, thanks for the reply.
The device is a Synology RT2600ac (combined internet and WLAN Router).
I found no specific options for SIP ALG
I only have an option “SIP Pass-trough” (is active now)
I have searched for SIP-ALG (to the device) and only found, that deactivate “SIP Pass-trough” also would deactivate SIP-ALG.
But I think, “SIP Pass-trough” has to be activated for the phones to work…?
Further - as I wrote - we never had such problems (the phone has worked since months without any problem)...

 

[JohnS_3CX]

Hosted by 3CX does not support STUN devices because sooner or later you will have issues with them.

The N510 is not even supported at all for SBC or STUN.

 

[FredyWenger]

Sorry, but your answer don't help...
As I wrote, this has worked months without problems.
Further, the Gigaset works since years now without problems.
It can't be, that the customers have to install and SBC in any home office with one or two devices ?!?
We are a paying customer - so please answer my questions...
So... how can it (technical) be, that a "phantom" phone is still showed on the 3cx console, when it is turned off since hours?
I think, "SIP Pass-through" has to be activated on the firewall to serve the IP phones?
-> Yes or no?
Is there a way to delete the "phantom" phone on the 3cx console?

Thank for a usable feedback.

 

[JohnS_3CX]

Hi Fredy,

Sorry, please allow me to explain a little better.

As I have explained in may other STUN related posts which you can search on the forum with my name, if you do not run the phones in the 3CX supported way, the results will be unpredictable. Sometimes it will work fine, until one day it doesn't work for no apparent reason.

There's 100s of posts in our forum about STUN issues showing these same points being brought up often again and again:

- It used to work fine
- I see ghost entries
- My devices have failed registrations
- We have missed inbound calls
- We have one-way audio or no audio

We simply do not know how your firewall and ISP modem will decide to act at any given time, this is what makes STUN so unpredictable.

This is why we:

a) made the SBC that bypasses all those problems

and

b) made this article I shared above so you can manually bypass the NAT, ALG and other restrictions, if you wish to do so.

Please try to ensure you have actually done everything in the article at least.
Almost everyone who had this issue in the past was able to solve it this way.

As for your firewall settings, unfortunately I cannot help you with that because I do not know that firewall + ISP combo. This is something you will have to investigate yourself because we are not in a position to know how each of the 1000s of firewall models out there behave.

I hope this was more helpful!

 

[FredyWenger]

I hope this was more helpful!

It was a bit more helpful - at least you have wrote more details...
As I wrote, we have a SBC in use for the phones in the company (as we have some servers running, it was no problem to install and run the SBC on an already existing server).
This looks completely different, if you have some phone(s) in a home office or wherever.
One ("THE") big advantage of IP phones should be "plug & play" (not plug and pray).
-> Configure an IP phone, put it in wherever and... it... should... work
You (3cx) cannot expect, that your customers want to install a SBC at every small location.
So... 3cx should do more here to support their customers to exactly this theme...

To our problem - maybe this helps somebody:
If have done various tests....
One of the tests was, to temporarily put off the Synology RT2600ac (combined internet and WLAN Router) at the home office.
A few minutes later, the "ghost" phone on the 3cx has disappeared.
This was a sign for me, that the router/firewall has a role to the problem (seems to have polled to the 3cx)...
I then have disabled “SIP Pass-trough” on the firewall (Synology RT2600ac), as there is not option to disable only SIP ALG
And.. it seems as this have solved the problems:
- No "ghost" phone on the 3cx console
- Anything seems to work as it should again: Yealink SIP-T46S and also the Gigaset Dect (whereby we had not problem with it in contrast to he Yealink)

I have no idea, why the problem was coming from one day to the other and further don't know, if the option “SIP Pass-trough” was active before (when it has worked).
I have for sure not changed the option, but we had a power break (maybe, this has activated the option, but there is a small change form my point of view).
However.. disabling “SIP Pass-trough” on the firewall seems to have solved the issue at least for now (hope this holds).

 

[JohnS_3CX]

Hi Fredy,

I'm happy to hear that the issue has been solved for now.

One ("THE") big advantage of IP phones should be "plug & play" (not plug and pray).
-> Configure an IP phone, put it in wherever and... it... should... work

Yes this is true, but only if you set it up like 3CX recommends and supports. This is a 3CX requirement so I would make sure that the port forwards are carried out as we described.


We describe this in our training material: https://www.3cx.com/3cxacademy/videos/intermediate/configuring-remote-extensions/