We have a headquarter, a disaster recovery site and 21 branches. We are planning on migrating our FR WAN to MPLS. Some branches have DMVPN for link backup. We run OSPF in both LAN and WAN, including the DMVPN. There are about 35 routers.
However, MPLS service providers prefer BGP as the routing protocol for the WAN and the one with best prices even doesn't support OSPF.
So I want to hear from you what you think about migrating from OSPF to iBGP as our WAN routing protocol.
I forgot to mention ... the HQ and DR will have different service providers. Some branches will have two service providers.