So I have just bought a 2nd Vigor 2866 to do Hot-Standby High Availability on WAN 2 (WAN Ethernet interface), which is my active WAN interface.

However I have realised that due to my ISP requires MAC spoofing on the WAN side, the unmanaged WAN gigabit switch connecting the master/active Vigor 2866 and slave/standby Vigor 2866 both to the ONT/WAN of my ISP, is going to potentially see the same MAC address from both Vigor 2866's.

Will this be a problem, or is the WAN interface of the slave/standby Vigor 2866 offline at a layer 2 level during normal circumstances? 

Regards: Elliott.