A route map is a named set of match conditions and parameter settings that the device can use to modify route attributes and to control redistribution of the routes into other protocols.
A route map consists of a sequence of instances, the equivalent of rows in a table. The device evaluates a route according to route map instances in ascending numerical order. The route is first compared against instance 1, then against instance 2, and so on. When a match is found, the device stops evaluating the route.
By default, route maps that are applied in IPv4 address family configuration mode with the neighbor route-map command apply only to IPv4 unicast address prefixes. To apply route maps to IPv6 unicast address prefixes, use the same command in IPv6 address family configuration mode.
The route maps are applied as the inbound or outbound routing policy for neighbors under the address family. Configuring separate route maps under each address family type simplifies managing complicated or different policies for each address family.