Route-Map
A route-map consists of ACLs and set of
directives that define the egress interfaces for forwarding the flow.
A route-map consists of a sequence of instances, the equivalent of rows in a table. The device
evaluates an incoming packet according to route-map instances in ascending numerical
order. The incoming packet is first compared against instance 1, then against instance
2, and so on. When a match is found, the device stops evaluating the incoming
packet.
Route-maps can contain match clauses and set statements. Each
route map contains a forward-action permit or
forward-action deny statement that modifies the
behavior of the route-map instance:
- If the route-map contains a forward-action
permit statement, the access lists present in the match statement
are used to match against incoming packets, and matched packets are forwarded
according to the access lists. If the packets do not match the access lists in the
match statement, the packets are passed to the next instance in the same route-map.
If the packet does not match any of the access lists in the route-map, it is
dropped.
- If the route-map instance contains a
deny
statement, the matching route-map instance is skipped. The route-map instance does
not program the access lists in the match statements, and packets that match, skip
that route-map instance.
- If an incoming packet does not match any
access lists in the match statements of the route-map, the packet is dropped. This
is the default action. To change the default action, configure the last
match statement in the last instance of the route-map to a MAC
access list with a clause of permit any
any.
- If there is no match statement,
route-map instance is skipped like the forward-action
is set to deny.
If the route-map contains set statements, packets that are permitted by the route-map
match
statements are forwarded according to the set statements.
