Failover to a different path
in the topology above, I would like R1 to always use the Path to R2. The only time it should use the path to R3 is when the link between R1 and R2 is down.
I am configuring OSP between all Routers, I also want to use BFD (Bidirectional Forwarding Detection), so that the link failure will be detected faster than OSPF , and once detected the path will switch automatically to R3.
I believe that there is HSRP ,VRRP,GLBP and other protocols that can do that. I just wonder if it can be done without those protocols. Unless if I am confused, probably BFD is used by the protocols I have previously indicated (HSRP ,VRRP,GLBP )