Transparent monitors mark nodes down

Almost but not quite right. If 203.0.113.1 is the gateway(router) then you need to set the destination to something that is beyond that router that will need to use a router to be reached. Say like 8.8.8.8. If the probe is able to reach 8.8.8.8 while using the router 203.0.113.1 it shows that the router is working.

You do not set the destination IP with the router address. You set it to something on the far side of the router.

I want to comment on the other thing you mentioned about the wideips. For this to work in that way you need to: - create an ltm pool with the two routers in it - apply the transparent gateway_icmp monitors to it as we have been discussing - create a default route that uses the pool - configure a Links in the DNS section each router in the gateway pool and apply the bigip_link monitor to each.

The bigip_link monitor will get the status internally from the monitors configured in the default gateway pool. If a router is marked down by the pool member the bigip_link monitor will mark it down. Any resource in the DNS section that relies on that link to work will inherit that down status as well.

That is how the wideips will get marked down if the link they rely on is failing health checks.