V20 Can't login to web console of T48Us (3) or W70B

[technomojo]

New install of V20 on Amazon LightSail in September. All rigorously tested and working fine after installation. 3 x T48Us, all set as router phones and one W70B with one handset.

At some stage in the 2 months since the initial setup, the W70B stopped registering. Not sure when this happened exactly, the client didn't raise it with me (I just happened to notice it while making other changes).

Then I discovered that the web console password in the 3CX management console didn't allow me to login to the W70B. Same story for all the T48Us. Could the W70B have become unregistered because of this password issue with the T48Us?

My plan is to manually factory reset and reprovision all 4 of the phones.

Anyone know why or how this might have happened?

Some further background: the client (system owner) received a legit email (from [email protected]) today saying his license will expire tomorrow. The email quotes a different license number to his. Tomorrow will mark exactly 2 months since the license was activated, though the management console is showing an expiry exactly 12 months after activation. Links in the email are all legitimate.

Thanks in advance.

 

[JohnS_3CX]

Is there an SBC in place where the phones are located?

 

[technomojo]

Is there an SBC in place where the phones are located?

Hi John,

Thanks for your reply.

No SBC, just the router phones.

I think we got to the bottom of the issue. With the help of the tech team at my local SIP provider, we were able to reset the web console password of each of the phones and login to take a look at the configuration. It seems that the ISP had auto-provisioned them - we found the .cfg URL in the console.

What I don't understand is how this was possible after the phones were provisioned by 3CX. How did the ISP circumvent the web console password? The strange thing is that the T48Us continued to work, allowing users to take and make calls. I couldn't restart or reprovision them from 3CX though.

The other question is why the ISP would autoprovision phones that they didn't provide, which I'll follow up with them!

 

[JohnS_3CX]

Very strange indeed, let us know how it goes.

Make sure there is no DHCP Option 66 on your LAN, it can override the phones and send them to a different provisioning server.

Same if they were added to a Yealink RPS account other than the 3CX one.