I have two layer 2 back-haul fibers from a remote part of my network. I need to load balance across both fibers.
This part of the network is a separate OSPF area. I have tried using OSPF to load-balance but it does not work. Also tried bonding. No luck
What device is the other end of that link?
Is it a switch? Or another MikroTik router?
You should be absolutely fine with bonding and balance-rr. Unfortunately, the fewest switches do this as well. And be aware that balance-rr can cause a lot of out-of-order packets.