Multiple WAN for testing

Fresher

Hello. Im trying to set up additional WAN interface for testing purposes. But getting this error:

Error
Subnet on this interface overlaps with another interface

The interface settings should be the same as my default WAN X1, cause it has ISP static IP and I want to test X8 which will be fiber connection. How to set it up?

TZ570W

Arkwright

You can't have multiple WAN interfaces in the same network. So you would have to change X1 to be something else, before assigning X1's old IP to X8.