Available for S-Series and P-Series PBXs.
The trunk configuration screenshot is as follows
Username: provided by the ISP
Authentication Name: provided by the ISP
The default port is the LAN port, and the WAN port is connected to the dedicated line (DU Trunk).
Configure the PBX network settings as the below picture:
Add a WAN port DNS (provided by the ISP) to the LAN port. Usually, add 18.104.22.168 to the LAN Preferred DNS Server. Add 22.214.171.124 (or 126.96.36.199) as the Alternative DNS.
Add the DNS (usually the ISP will provide 2 DNS) to the static route to make it go through the WAN port.
For example, the below picture add the DNS 10.62.215.44
Need to add another DNS as well.
For the DU trunk, need to add another fixed destination to avoid no voice issue.
See the below picture, the destination IP is fixed 10.59.0.0/255.255.0.0
For the DU trunk, the codec needs to select u-law and a-law.