why?
what are the inside and outside interfaces plugged into?
if you want proper redundancy you should have
|Switch 1| -> | PIX | -> |Switch 3|
|Switch 2| -> |PIXFO| -> |Switch 4|
So Switch 1 and 2 are trunked/stacked together, and so are 3 and 4.
Is that what you have atm?
edit: damn board stuffed up diagram
Cheers
Dave