Discard route enables you to prevent forwarding traffic to specific networks. You can configure a static route that drops all packets destined to the route. This is called a discard route, indicated by the null0 parameter.
Procedure
Use the ip route<network><mask>null0 CLI command.
Note:
You cannot configure tracking on a discard route.
Example
For example, the command ip route 134.66.0.0 16 Null0 configures the network 134.66.0.0 16 as a discard route