[c-nsp] host availability monitoring / OER

[Christian MacNevin]

Hi

I have a requirement to provide source redundancy for an SSM multicast  
feed. In terms of routing, an anycast routing setup
seems to make sense, with two sources sending a stream with the same  
source address and the routing table sorting
it out.

So what I'm thinking is that each of the directly connected ciscos  
(3560s in this case) need to have static routes pointing to
the physical addresses of directly attached hosts. Their common next  
hop with which they speak ospf would then make
the best path decision. All fine. The issue of course becomes when we  
expect to see failover, how does the route get withdrawn
from the table? If I make the access ports into routed ports, then a  
link-down event will result in a withdrawn route, which is fine.
But obviously this is less than optimal, as I'd like to have a vlan  
here for scalability.

So is there another option somebody can think of? What I'm thinking of  
is something like OER on either the directly-connected
devices or the next hop doing ip sla echo responses to influence the  
metric of a route or something to that effect.

Any thoughts?

Thanks
Christian