Switch caching host routes?

mfieldhouse

Hi, we have a production switch which somehow has a routing table with host routes in it.
It is a WS-C3550-24-PWR with IOS 'c3550-ipbasek9-mz.122-50.SE1.bin'

'ip routing' is not present in the config, no routing protocols are running or static routes configured. However, when doing a 'show ip route', the following is displayed:

Host Gateway Last Use Total Uses Interface
172.21.1.191 172.16.35.253 0:00 73738 Vlan1
172.21.14.242 172.16.35.253 0:00 1138 Vlan1
172.21.1.239 172.16.35.248 0:00 812685 Vlan1

This is causing a problem as the route to '172.21.1.239', our network monitoring system, is outdated as that gateway no longer exists.

Does anyone know how to clear this route table and provide any information on how it was formed as I've never seen this before.

Thanks

mfieldhouse

Fixed! The routes which were being shown were actually ICMP redirects. They can be cleared using 'clear ip redirect'.

dtlokee

You can clear them but they may come back if there were there before, the real culprit is going to to be the routing table of the defualt gateway for that switch.