Configuring BGP4
December 2005 © Foundry Networks, Inc. 21 - 49
For routes that match all of the match statements, the route map’s set statements can perform one or more of the
following modifications to the route’s attributes:
• Prepend AS numbers to the front of the route’s AS-path. By adding AS numbers to the AS-path, you can
cause the route to be less preferred when compared to other routes on the basis of the length of the AS-path.
• Add a user-defined tag to the route or add an automatically calculated tag to the route.
• Set the community value.
• Set the local preference.
• Set the MED (metric).
• Set the IP address of the next hop router.
• Set the origin to IGP or INCOMPLETE.
• Set the weight.
For example, when you configure parameters for redistributing routes into RIP, one of the optional parameters is a
route map. If you specify a route map as one of the redistribution parameters, the router will match the route
against the match statements in the route map. If a match is found and if the route map contains set statements,
the router will set attributes in the route according to the set statements.
To create a route map, you define instances of the map. Each instance is identified by a sequence number. A
route map can contain up to 50 instances.
To define a route map, use the procedures in the following sections.
Entering the Route Map Into the Software
To add instance 1 of a route map named “GET_ONE” with a permit action, enter the following command.
FESX424 Router(config)# route-map GET_ONE permit 1
FESX424 Router(config-routemap GET_ONE)#
Syntax: [no] route-map <map-name> permit | deny <num>
As shown in this example, the command prompt changes to the Route Map level. You can enter the match and
set statements at this level. See “Specifying the Match Conditions” on page 21-50 and “Setting Parameters in the
Routes” on page 21-52.
The <map-name> is a string of characters that names the map. Map names can be up to 32 characters in length.
The permit | deny parameter specifies the action the router will take if a route matches a match statement.
• If you specify deny, the Layer 3 Switch does not advertise or learn the route.
• If you specify permit, the Layer 3 Switch applies the match and set statements associated with this route map
instance.
The <num> parameter specifies the instance of the route map you are defining. Each route map can have up to
50 instances.
To delete a route map, enter a command such as the following. When you delete a route map, all the permit and
deny entries in the route map are deleted.
FESX424 Router(config)# no route-map Map1
This command deletes a route map named “Map1”. All entries in the route map are deleted.
To delete a specific instance of a route map without deleting the rest of the route map, enter a command such as
the following:
FESX424 Router(config)# no route-map Map1 permit 10
This command deletes the specified instance from the route map but leaves the other instances of the route map
intact.
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