I have a wireless network serving an outdoor location, configured as a ring. There are two gateways (DSL), at opposite (geographical) ends of the ring. OSPF is set up in simple fashion to deliver traffic to the closest gateway, and to reroute all traffic to the working gateway if a gateway or intervening link goes down. This configuration has been working acceptably for many years.
Recently, we encountered a situation where one gateway (phone company) feed failed, but the accompanying modem stayed up... showing a "disconnected" state on its status page, but still delivering a DHCP address to our MikroTik equipment. Since the modem's own address was up and responding, OSPF considered the connection up, and kept shipping all the traffic from that side of the ring into the broken gateway, timing out on everything, but never switching the routing to the working gateway.
I ended up temporarily manually disabling the interface on that side to trigger OSPF, but only after a significant delay of days before I realized something was wrong (the client didn't report anything).
Other than scripting, which is inelegant, time-consuming, and error-prone, is there some more simple configuration additive I can apply that would inform OSPF that despite having single-hop connectivity to the modem, the gateway service itself is actually dead?