Tips for configuring Gradwell multi-number trunks

[atommo]

Just putting this out there as I've had a few issues configuring multi-number trunks on 3CX with Gradwell. I finally got to the bottom of it!

The issue
Configuring individual numbers per trunk was fine, but when trying to add additional numbers through the same trunk, the numbers wouldn't dial in. I was seeing an issue like in this thread: https://www.3cx.com/community/threads/407-proxy-authentication-required.55960/

In the past, I have called up Gradwell and they made changes which I wasn't sure about, and then it worked. I was under the impression the fix was something to do with amending the way numbers were entered on the 3CX server to include a wildcard asterisk at the start, such as *123456789

That wildcard asterisk might help, but it wasn't the whole root cause.

The solution
On Gradwell's portal, you can go to 'Core Setup' and then 'Phone Numbers'. In there, you can specify the trunk each number should use. You need to specify the Outbound SIP trunk configured on Gradwell that your 3CX server connects to. After that, your issue should be sorted!

The problem had been bugging me for months and I'd even had to go through the workaround of making ~80 unique SIP trunk credentials (a set of credentials for each number) on Gradwell's portal before I discovered this solution.

 

[atommo]

There is more... I tried this for another customer and had issues. After talking with Gradwell some more, they clarified:

The issue was because the problem numbers were originally setup for IP-Based SIP and this has a destination setup for it under Inbound Trunks.

Each problem number which has an individual destination would need to be deleted in that list. These would show as the DDI with the destination having a format sip:[number]@[sip server]

Then back in the core setup number area, you need to associate the numbers with the outbound SIP trunk configured on the 3CX server. This can take up to 15-20 minutes to take effect after configured.