I’ve reviewed a number of threads on the forum regarding WAN failover. It seems like failover should work by default in the current firmware (3.009 or 3.022), and is configured to prioritize WAN ethernet, then available WiFi APs, then USB modems / tethered devices, and lastly the internal LTE module.
I have an X750 plugged into an upstream network via ethernet cable to its WAN port. The X750 is receiving its IP on this network via DHCP, and uses the upstream router for DNS. When I unplug the ethernet cable from the WAN port, failover to the X750’s internal LTE module works as expected. However, when I leave the ethernet cable plugged in and power down the upstream router, the X750 does not failover to its internal LTE module’s connection.
What is triggering failover from WAN port to other interfaces? Is the physical ethernet cable connection being sensed and, when removed, triggering failover? Or does mwan3 ping a control IP at regular intervals to determine if the current gateway with the highest priority metric is still connected to the internet? How come the X750 does not failover when its upstream DHCP/DNS gateway router connected via WAN ethernet port is powered down?
Thanks for your assistance.