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To create route map instances, use these commands. There is no limit to the number of set commands per
route map, but the convention is to keep the number of set filters in a route map low. Set commands do not
require a corresponding match command.
Configure a Route Map for Route Redistribution
Route maps on their own cannot affect traffic and must be included in different commands to affect routing
traffic.
Route redistribution occurs when the system learns the advertising routes from static or directly connected
routes or another routing protocol. Different protocols assign different values to redistributed routes to
identify either the routes and their origins. The metric value is the most common attribute that is changed to
properly redistribute other routes into 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 Tengigabitethernet interface 0/0 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 0/0
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.
Access Control Lists (ACLs)
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Troubleshooting
