3CX to 3CX calls no longer working

[Eoin Colley]

I have a 3CX PBX, and so does my client. I added an extension for myself to their PBX, and I connected to it as a (Generic SIP) trunk from my own. When they dial my extension, it rings on my main ring group. On my own PBX, I created an outbound rule so that, with a prefix, I can dial any of their extensions. I even created a second outbound rule so I could dial any outbound number through their PBX.
This worked perfectly until a few weeks ago. Now, the calls still come in, but I can no longer dial their extensions, or out through their trunks. I have tried recreating the extension and the trunk several times, but the result is always the same, 404 User unknown.

Here is a typical log entry:

10/22/2018 11:49:34 AM - Leg L:46.2[Line:10000>>866] is terminated: Cause: 404 User unknown./INVITE from nnn.nnn.nnn.nnn:5060
10/22/2018 11:49:34 AM - Call to T:Line:10000>>866@[Dev:sip:[email protected]:5060] from L:46.1[Extn:204] failed, cause: Cause: 404 User unknown./INVITE from nnn.nnn.nnn.nnn:5060
10/22/2018 11:49:34 AM - [CM503003]: Call(C:46): Call to <sip:[email protected]:5060> has failed; Cause: 404 User unknown./INVITE from nnn.nnn.nnn.nnn:5060
10/22/2018 11:49:34 AM - [CM503025]: Call(C:46): Calling T:Line:10000>>866@[Dev:sip:[email protected]:5060] for L:46.1[Extn:204]
10/22/2018 11:49:34 AM - [CM503027]: Call(C:46): From: Extn:204 ("yyyy 204" <sip:[email protected]:5060>) to T:Line:10000>>866@[Dev:sip:[email protected]:5060]
10/22/2018 11:49:34 AM - [CM503004]: Call(C:46): Route 1: from L:46.1[Extn:204] to T:Line:10000>>866@[Dev:sip:[email protected]:5060]

Can anyone suggest what's going on? Was there an upgrade which broke it?

 

[craigreilly]

Why not simplify and create a bridge?

 

[Eoin Colley]

Why not simplify and create a bridge?

Because I don't want to (and can't) integrate the extension numbers across the two systems. Plus, it worked. Plus, it should work!

 

[saint_]

I second Craig. Create a bridge, and if you don t want everybody to call everybody, just limit who to call in the bridge prefixes.

 

[YiannisH_3CX]

Hello @Eoin Colley

I will to agree that the best way to implement this is by creating a bridge between the 2 systems. The error you are getting seems to related to source identification. The phone system you are calling either does not match the number you are calling to a DID of the system or because the DIDs you are using are too short (as they are extensions of the system).