IPSEC heartbeat in CISCO

[TC Wolsey]

You indicate that you want to detect the error and re-route traffic. If
you want to automagically re-route traffic I agree with Ryan that a
routing protocol is the way to go, although I think that the link-states
(OSPF and I/IS-IS) are probably more problem to setup over the tunnel than
they are worth. I would suggest I-BGP. Of course dynamic routing does not
throw up any flags when routes fail, so if you want some notification when
you switch to a more expensive path that is a different issue.

Regards,
tcw