Concept Guide

a routing protocol. Other attributes that can be changed include the metric type (for example, external and internal route types
in OSPF) and route tag. Use the redistribute command in OSPF, RIP, ISIS, and BGP to set some of these attributes for
routes that are redistributed into those protocols.
Route maps add to that redistribution capability by allowing you to match specific routes and set or change more attributes
when redistributing those routes.
In the following example, the redistribute command calls the route map static ospf to redistribute only certain static
routes into OSPF. According to the route map static ospf, only routes that have a next hop of interface 1/1 and that have a
metric of 255 are redistributed into the OSPF backbone area.
NOTE: When re-distributing routes using route-maps, you must create the route-map defined in the redistribute
command under the routing protocol. If you do not create a route-map, NO routes are redistributed.
Example of Calling a Route Map to Redistribute Specified Routes
router ospf 34
default-information originate metric-type 1
redistribute static metric 20 metric-type 2 tag 0 route-map staticospf
!
route-map staticospf permit 10
match interface TenGigabitEthernet 1/1
match metric 255
set level backbone
Configure a Route Map for Route Tagging
One method for identifying routes from different routing protocols is to assign a tag to routes from that protocol.
As the route enters a different routing domain, it is tagged. The tag is passed along with the route as it passes through different
routing protocols. You can use this tag when the route leaves a routing domain to redistribute those routes again. In the
following example, the redistribute ospf command with a route map is used in ROUTER RIP mode to apply a tag of 34 to
all internal OSPF routes that are redistributed into RIP.
Example of the redistribute Command Using a Route Tag
!
router rip
redistribute ospf 34 metric 1 route-map torip
!
route-map torip permit 10
match route-type internal
set tag 34
!
Continue Clause
Normally, when a match is found, set clauses are executed, and the packet is then forwarded; no more route-map modules are
processed.
If you configure the continue command at the end of a module, the next module (or a specified module) is processed even
after a match is found. The following example shows a continue clause at the end of a route-map module. In this example, if a
match is found in the route-map “test” module 10, module 30 is processed.
NOTE: If you configure the continue clause without specifying a module, the next sequential module is processed.
Example of Using the continue Clause in a Route Map
!
route-map test permit 10
match commu comm-list1
set community 1:1 1:2 1:3
set as-path prepend 1 2 3 4 5
continue 30!
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Access Control Lists (ACLs)