You can control the importation of static routes into the routing
and forwarding tables in a number of ways. Primary ways include assigning
one or more of the following attributes to the route:
retain—Keeps the route in the forwarding
table after the routing process shuts down or the device reboots.
For more information, see Route Retention.
no-readvertise—Prevents the route from
being readvertised to other routing protocols. For more information,
see Readvertisement
Prevention.