Foundry Networks FESX User Manual

Foundry Configuration Guide for the FESX, FSX, and FWSX
21 - 60 © Foundry Networks, Inc. December 2005
NOTE: To change any of the parameters, you must specify all the parameters with the command. If you want to
leave some parameters unchanged, enter their default values.
Using a Route Map To Configure Route Flap Dampening for Specific Routes
Route maps enable you to fine tune route flap dampening parameters for individual routes. To configure route flap
dampening parameters using route maps, configure BGP4 address filters for each route you want to set the
dampening parameters for, then configure route map entries that set the dampening parameters for those routes.
The following sections show examples.
To configure address filters and a route map for dampening specific routes, enter commands such as the
following:
The address-filter commands in this example configure two BGP4 address filters, for networks 209.157.22.0 and
209.157.23.0. The first route-map command creates an entry in a route map called “DAMPENING_MAP”. Within
this entry of the route map, the match command matches based on address filter 9, and the set command sets
the dampening parameters for the route that matches. Thus, for BGP4 routes to 209.157.22.0, the Layer 3 Switch
uses the route map to set the dampening parameters. These parameters override the globally configured
dampening parameters.
The commands for the second entry in the route map (instance 10 in this example) perform the same functions for
route 209.157.23.0. Notice that the dampening parameters are different for each route.
Using a Route Map To Configure Route Flap Dampening for a Specific Neighbor
You can use a route map to configure route flap dampening for a specific neighbor by performing the following
tasks:
• Configure an empty route map with no match or set statements. This route map does not specify particular
routes for dampening but does allow you to enable dampening globally when you refer to this route map from
within the BGP configuration level.
• Configure another route map that explicitly enables dampening. Use a set statement within the route map to
enable dampening. When you associate this route map with a specific neighbor, the route map enables
dampening for all routes associated with the neighbor. You also can use match statements within the route
map to selectively perform dampening on some routes from the neighbor.
NOTE: You still need to configure the first route map to enable dampening globally. The second route map
does not enable dampening by itself; it just applies dampening to a neighbor.
• Apply the route map to the neighbor.
FESX424 Router(config)# router bgp
FESX424 Router(config-bgp-router)# address-filter 9 permit 209.157.22.0
255.255.255.0 255.255.255.0 255.255.255.0
FESX424 Router(config-bgp-router)# address-filter 10 permit 209.157.23.0
255.255.255.0 255.255.255.0 255.255.255.0
FESX424 Router(config-bgp-router)# exit
FESX424 Router(config)# route-map DAMPENING_MAP permit 9
FESX424 Router(config-routemap DAMPENING_MAP)# match address-filters 9
FESX424 Router(config-routemap DAMPENING_MAP)# set dampening 10 200 2500 40
FESX424 Router(config-routemap DAMPENING_MAP)# exit
FESX424 Router(config)# route-map DAMPENING_MAP permit 10
FESX424 Router(config-routemap DAMPENING_MAP)# match address-filters 10
FESX424 Router(config-routemap DAMPENING_MAP)# set dampening 20 200 2500 60
FESX424 Router(config-routemap DAMPENING_MAP)# router bgp
FESX424 Router(config-bgp-router)# dampening route-map DAMPENING_MAP

Foundry Networks FESX Specifications

General

Brand	Foundry Networks
Model	FESX
Category	Switch
Language	English