centurylink business registration

[stty]

We are using 3cx version 15.5.9348.3 on linux with centurylink business sip trunks configured by following this document. The provider is requiring SIP REGISTER messages to have the outbound proxy's IP address in the request-line instead of the Registrar/Server/Gateway Hostname. For example, they need it to read "REGISTER sip:216.206.64.81:5100 SIP/2.0" instead of "REGISTER sip:voip.centurylink.com:5100 SIP/2.0." Is there a place in the GUI or a parameter setting where this can be specified?

 

[cobaltit]

Outbound Parameters tab on the trunk

 

[stty]

Thanks, but those apply to INVITE messages, not REGISTER messages.

 

[NickD_3CX]

Did CenturyLink tell you this? I distinctly remember it working with an their registrar in the RURI when we were running the interop with them.

But before getting to specifics, what is the exact problem you are facing? Not registering at all? Intermittent disconnections?
Also, has it ever worked?

 

[stty]

The trunks register correctly and calls work until a period of time passes, and while the trunks show registered in the 3cx GUI and in the provider's portal, their SBCs send 403 forbidden messages and calls begin to fail. Re-registering the trunks in the GUI temporarily resolves the problem. The required format is shown on the bottom of page 8 of the CenturyLink IQ SIP Trunk Interface Requirements document, if you still have it. I'd like to get to specifics as soon as possible because the provider's engineering team will not proceed until that requirement is met.

 

[NickD_3CX]

Retesting will take time, probably weeks, and I am just saying this to set expectations.

Yes, I remember the requirement but from the tests we had run I don't remember this being a problem, hence the reason why we included the template in 3CX, because this can't change, but despite that it worked.

In the meantime, as you can initially register fine, I have a small doubt that this is the issue after hearing what is happening, but I have a question. After how long after you press the "re-register" button do calls start failing. Try to be as precise as possible so that I can check the test results we have and see if there is something that could be causing this.

 

[stty]

I share the same doubt, but this has become an impasse with the provider's support team. The first time it happened was about 5.5 hours after the re-registration, then again about four hours after that. It's difficult to search through the activity log using the load more button in the GUI. Where is that log stored on the server?

 

[NickD_3CX]

The activity log data in in the .blref/.blrec files that can be opened with Bin Log Viewer, but:
1) the recycle quite often
2) they are sometimes overly complicated to read through

I would suggest a slightly different approach as the issue lies with a response from the provider, so a capture should do fine.

Do the following:

1. Start capturing using a capturing filter something like: host [centurylink outbound proxy ip] and port 5100
2. Restart the 3CX SIP Server
3. Wait the 5-6 hours
4. Try to make a call.

Then you will have a full registration sequence from the start to the to the problem. Maybe that could point in the right direction. If you get the capture and you want a second opinion, send me a PM with a download link and I could have a look.

 

[stty]

Thank you for the suggestion. The provider spent most of yesterday going over captures from their system, but I will try this so I can see them for myself. In order to clarify, did you mean it is not possible to change the request-line in the REGISTER message to meet their requirement?

 

[NickD_3CX]

...did you mean it is not possible to change the request-line in the REGISTER message to meet their requirement?

Yes, that is correct.