We have a core switch, mpls ce router ( we are the customer) and a firewall that faces the internet.
All 3 devices run ospf. And all 3 devices are in the same subnet. Tonight we rebooted the core switch. When the switch came back up, i noticed the router and firewall had no connectivity to the switch, but had connectivity to outside networks. The switch seemed to be able to ping all local hosts, but not the firewall or router. The mpls routers' logs showed several messages stating " dead timer expired"
Even if ospf adjacency was lost, these devices should have still been able to speak since they are in the same subnet
So what happened"