[Mobile Router] How to configure the device to use it as a backup WAN for a USG FLEX H?

Zyxel_Tina

If your goal is to use the mobile router as a cellular backup WAN while keeping your primary Internet connection on a fixed-line PPPoE service, we recommend letting the USG FLEX H manage the WAN failover.

Configure the primary PPPoE connection with VLAN directly on P1 of the USG FLEX H, connect the mobile router, such as FWA510/FWA515, to P2, and configure the mobile router as the backup WAN connection. Then create a WAN Trunk on the USG FLEX H with P1 as Active and P2 as Passive, and use the trunk as the Default Trunk.

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This approach allows the USG FLEX H to manage the primary and backup WAN connections and perform the failover between them.