HA setup on different hardware

[c00kie55]

i have a pfsense box with 6 x 10Gbe (iglx) interfaces now i would like to setup a backup node but since only active/passive mode is supported i dont want to waste so much hardware on the passive node.
my plan would be to have 3 Gigabit interfaces, 1 for wan (em0), 1 for sync (em1) and then alot of vlans on the last interface(em2). is this possible or do i really need to have 2 identical boxes?

[Derelict]

Works best if you do.

In general, if it is worth HA it is worth doing right. Especially if you are responsible for moving multi-gigabits of traffic around.