3CX Treating Two Phones as One

[365E]

I have an extension that has 2x T48s'.
One phone is in a home office, the other is in the main office.
We keep losing the provisioning on one phone or the other randomly.
Only one phone will provision at a time. 3CX is acting like both phones are one/the same device.
I noticed 3CX listed an identical MAC for both phones at one point. When I provision the second phone it will provision but show no service until I disconnect the other phone.
I am fed up and ready to delete the extension & recreate it as a last resort, but the user involved is the CEO so I don't want call history, chats, etc. to get messed up.

Anybody seen a similar strange issue?
All firmware is up to date & supported.

 

[Saqqara]

How is the main office phone provisioned ?

How you trying to provision the home office phone ?

Guessing your are using stun for the office phone

 

[JohnS_3CX]

You are clearly using STUN, this is a typical issue when setting up STUN without taking care of the networking requirements

We would recommend to move away from STUN, and instead go ahead and install an SBC at the CEO's home and it will make all your problems go away.

The SBC works on:

- VM
- Dedicated PC
- Raspberry Pi

 

[365E]

yes, we are using stun in an Azure hosted 3cx instance.

There are issues with another phone in the office always loosing registration...no matter what I can't get it back online.
The only thing to change in 18 months is...nothing...just issues out of nowhere.
The other office phone gets all the settings and shows up in the phone list for a moment, then disappears and the account status on the phone reads "Register Failed".
I would rather figure out why it was working perfect for 18 months, but now nothing works vs. throw SBC's at it.

 

[SweetAction]

As for what changed... could be the Modem/Firewall or even internet service at the home location changed.

STUN is great - if all your equipment is STUN friendly. When it isn't... now it's off to the races to make it work.

At the end of the day is boils down to... the 3CX server needs to send a packet to the phone. Anything between the phone and the 3CX server needs to pass that packet along. If the equipment can't/won't do so, it won't work.

How do you have 2 physical devices with the same MAC?

 

[365E]

No clue how 3CX was treating both phones as one. I noticed both phones with different WAN IPs listed the same MAC. Strange, eh? Then it switched back and stopped seeing double after I factory reset one of the phones.

In this case, I ended up regenerating the extension creds, then incremented the SIP & RTP ports by 1 & 20 per STUN extension and...boom goes the Dynomite

I'm just going to aggressively push Bluetooth headsets for use with the desktop & mobile app going forward.

 

[JohnS_3CX]

I would rather figure out why it was working perfect for 18 months, but now nothing works vs. throw SBC's at it.

This would take a lot of time and effort, and is arguably a pointless exercise since you will still need to take some actions at the end. The SBC is a shortcut to the solution you want and will give you results without the pain of troubleshooting 6 packet captures across 2 networks

Using the apps is the best idea, they have their own way of tunnelling into the PBX (similar to what the SBC does for the phones) we update them regularly. If you don't explicitly need a deskphone, they are the best solution we can recommend