Call4tel

Using the NX32 as an SBC

The NX Series SBC setup is straightforward: the WAN port uses DHCP for connectivity, while the LAN port has a fixed IP (192.168.101.1) reachable at port 5448 with the default root/3cx credentials.

  1. Standard setup: download the Call4tel scanner tool, open the portal at 192.168.101.1:5448, go to Settings > SBC, and enter the SBC details.
  2. Repeat the process for a failover device using a different local IP, then configure that failover IP on all IP phones.
  3. Call4tel Failover (firmware 1.239+): configure primary and secondary SBC nodes with their own IPs, gateways, and netmasks in Settings.
  4. 3CX native setup: connect over SSH (port 998) and run 3CX's official failover script for cluster configuration.
  5. For HA clusters: use two identical machines on matching Debian/Raspbian versions, static LAN IPs on the same subnet, synchronized timezones, and matching interface names.