I have a question regarding what happens to a route when an interface is "disabled" vs. "deleted"? If you disable the interface, and routes are there - when a packet comes in, another interface, and needs to go out the "downed" interface, what happens?
My thought -- "ICMP Unreachable" is generated.
I have a scenaria where we are replacing a router interface with a firewall. So we don't have to change all the workstations, we are using the same IP of the router interface - it is dual-addressed on a single interface btw.
A route is then set on the router saying go to the IP of the FW (which is the same as the "downed" interface) to get to net x. I believe the router will send back ICMP unreachables as long as the interface is NOT deleted - only disabled. Your thoughts?
thanks