Clear the route cache on your Linux box

My environment: RH FC8 x86_64

Routing cache is a hash table in the kernel which contains recently used routes.  I have had a problem about traceroute on my Linux box after changing the default route, it still redirecting the packets to the old default gateway.  So what I have done is to remove the route cache.

To show the route cache:

ip route show cache

To clear the route cache:

ip route flush cache