Lumen Trunks and 3CX

N2MBacon

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I don't know why I'm having such a hard time setting up the CenturyLink/Lumen SIP trunks. I can't get them to register. We have an on-prem adtran from them where port 0/4 is x.x.x.249 passing SIP traffic to x.x.x.250. The trunks are registered to the Adtran I believe. When I do the quick setup with centurylink selected I input the main number I add the Trunk Group SIP ID as the user, the trunk password, uncheck 3-way authentication, change registrar/server from voip.centurylink.com to x.x.x.249 and leave outbound proxy alone. I have a secondary NIC on the 3CX system configured with the x.x.x.250 IP directly connected from NIC to 0/4 on the adtran.

I've tried numerous different ways to configure these trunks with the information from my welcome email from them and I cannot get the trunks to register. Any help would be appreciated.
 
This a complete unsupported scenario... CenturyLink is a supported sip trunk provider, but do you really have a real sip trunk from them?
 
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This a complete unsupported scenario... CenturyLink is a supported sip trunk provider, but do you really have a real sip trunk from them?
The SIP trunks are registered on the adtran as far as I know. We used a different on-prem PBX prior to this.
 
That didnt answer my question. Do you have a real sip trunk or what kind of product you are using? CenturyLink Sip Trunks are supported, but only without this crazy stuff here.
 
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That didnt answer my question. Do you have a real sip trunk or what kind of product you are using? CenturyLink Sip Trunks are supported, but only without this crazy stuff here.
Yes they are real SIP trunks.
 
Than connect them in the supported way and not via any other stuff.
 
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We also have CenturyLink (now Lumen) trunks that utilize an on premise Adtran device. We also have an on premise PBX that has a dedicated NIC to connect to the Adtran. We haven't had any issues with it, although, we took a different approach for the configuration. Perhaps details on our setup may assist you.

  • CenturyLink configured the Adtran with private/local IPs: the designated interface with an IP of 10.0.0.1 and pointed the SIP traffic to 10.0.0.2.
  • The PBX dedicated SIP interface is configured with the IP 10.0.0.2 and no gateway.
  • In 3CX, the trunk is configured with the "Generic SIP Trunk (IP Based)" template.
  • The "Main Trunk Number" field is populated with the primary TN we use. Auth fields are empty. The "Registrar" field contains the Adtran interface IP of 10.0.0.1 and the port is set to the standard 5060.

And that's it. It works and was actually fairly painless to get going, including having to work with CenturyLink, surprisingly.

Hope you find a resolution.
 
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We also have CenturyLink (now Lumen) trunks that utilize an on premise Adtran device. We also have an on premise PBX that has a dedicated NIC to connect to the Adtran. We haven't had any issues with it, although, we took a different approach for the configuration. Perhaps details on our setup may assist you.

  • CenturyLink configured the Adtran with private/local IPs: the designated interface with an IP of 10.0.0.1 and pointed the SIP traffic to 10.0.0.2.
  • The PBX dedicated SIP interface is configured with the IP 10.0.0.2 and no gateway.
  • In 3CX, the trunk is configured with the "Generic SIP Trunk (IP Based)" template.
  • The "Main Trunk Number" field is populated with the primary TN we use. Auth fields are empty. The "Registrar" field contains the Adtran interface IP of 10.0.0.1 and the port is set to the standard 5060.

And that's it. It works and was actually fairly painless to get going, including having to work with CenturyLink, surprisingly.

Hope you find a resolution.
This let us configure the trunk! Did you have to do anything special for your outbound routes? Ours will not allow any outbound with routes configured but we can receive calls thanks to your input!
 
This let us configure the trunk! Did you have to do anything special for your outbound routes? Ours will not allow any outbound with routes configured but we can receive calls thanks to your input!

Not that I recall. Here's our "Local Calls" rule:
  • Calls to numbers with a length of = 7
  • Calls from Departments = default department
  • Route 1 select the trunk, Strip no digits, prepend the area code

If it allows you to, try using the CenturyLink template but fill in the same IP details from the generic template you now have configured. I guess the only other settings changed from the default would be regarding "Caller ID Control" and "Codec priority" in the Options tab of the template. Here are those settings in the event it's useful:

  • Default Outbound Caller ID = primary TN
  • From Display Name = OriginatorCallerID Original Caller number will be sent
  • Remote Party ID Calling Party Display Name = Default
  • P-Asserted Identity Display Name = OriginatorCallerID Original Caller number will be sent
  • Codec priority = (1) PCMU, (2) PCMA, (3) G729
You should also double check that "Allow outbound calls" is ticked in the Options tab.
 

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