OSPF - 3 sites (2 subnets)

Hi All,

I’m looking for best way to achieve (almost) fully redundant system. I know the solution is a bit overkill, but customer has had bad experience with existing sites. The links aren’t perfect LOS so combination of different paths and different frequencies should help.

I have 3 sites.

Site A
Site B
Site C

Site A and B are already bridged using 3rd party wireless solution controlled by another party. This is staying.

Essentially Site C needs to talk to Site A.

Plan is
Primary Dual link from C to A - 900mhz and 2.4 on 1 x RB433 AH
Primary Dual link from C to B - 900mhz and 2.4 on 1 x RB433 AH

SITE A and B are same subnet (bridged)

I’ve done DUAL OSPF successfully before for PTP but not this scenerio. Can I assume that all 4 links are going to same subnet and just configure OSPF metrics on both boards ?

Will the third party wireless bridge have any arp issues etc ? Or can we just treat it like a switch ?

Thanks
Peter.