So I am attempting to move this setup into my UDM Pro firewall setup as a secondary WAN connection that will only be used when my primary connection fails. I am connecting the secondary WAN port on my firewall to the LAN2 connection on the GL.Net router. Everything works as expected as long as both the primary WAN and secondary WAN connections are active. I have validate this by ssh’ing to the MT13000 and performing a ping test, as well as setting a traffic rule on the UDM Pro to route specific traffic over WAN2.
When I disconnect the primary WAN connection, things stop working. When the primary and secondary WAN connections are active, the USB modem has a 100.x.x.x IP and traffic will route over WAN 2. If I disconnect WAN1 the USB modem IP changes to 192.168.1.2 and will not re-pull a good 100.x.x.x IP address from Verizon unless I either disconnect the GL.Net router completely from UDM Pro or reconnect the primary WAN connection.
I can’t figure out why this is happening or if the issue is on the GL.Net side or the UDM Pro.
Thoughts?