Removing Route Dampening From A Route - Foundry Networks FESX Manual

Configuring BGP4
To enable route flap dampening for a specific BGP4 neighbor, enter commands such as the following:
FESX424 Router(config)# route-map DAMPENING_MAP_ENABLE permit 1
FESX424 Router(config-routemap DAMPENING_MAP_ENABLE)# exit
FESX424 Router(config)# route-map DAMPENING_MAP_NEIGHBOR_A permit 1
FESX424 Router(config-routemap DAMPENING_MAP_NEIGHBOR_A)# set dampening
FESX424 Router(config-routemap DAMPENING_MAP_NEIGHBOR_A)# exit
FESX424 Router(config)# router bgp
FESX424 Router(config-bgp-router)# dampening route-map DAMPENING_MAP_ENABLE
FESX424 Router(config-bgp-router)# neighbor 10.10.10.1 route-map in
DAMPENING_MAP_NEIGHBOR_A
In this example, the first command globally enables route flap dampening. This route map does not contain any
match or set statements. At the BGP configuration level, the dampening route-map command refers to the
DAMPENING_MAP_ENABLE route map created by the first command, thus enabling dampening globally.
The third and fourth commands configure a second route map that explicitly enables dampening. Notice that the
route map does not contain a match statement. The route map implicitly applies to all routes. Since the route
map will be applied to a neighbor at the BGP configuration level, the route map will apply to all routes associated
with the neighbor.
Although the second route map enables dampening, the first route map is still required. The second route map
enables dampening for the neighbors to which the route map is applied. However, unless dampening is already
enabled globally by the first route map, the second route map has no effect.
The last two commands apply the route maps. The dampening route-map command applies the first route map,
which enables dampening globally. The neighbor command applies the second route map to neighbor
10.10.10.1. Since the second route map does not contain match statements for specific routes, the route map
enables dampening for all routes received from the neighbor.

Removing Route Dampening from a Route

You can un-suppress routes by removing route flap dampening from the routes. The Layer 3 Switch allows you to
un-suppress all routes at once or un-suppress individual routes.
To un-suppress all the suppressed routes, enter the following command at the Privileged EXEC level of the CLI:
FESX424 Router# clear ip bgp damping
Syntax: clear ip bgp damping [<ip-addr> <ip-mask>]
The <ip-addr> parameter specifies a particular network.
The <ip-mask> parameter specifies the network's mask.
To un-suppress a specific route, enter a command such as the following:
FESX424 Router# clear ip bgp damping 209.157.22.0 255.255.255.0
This command un-suppresses only the route(s) for network 209.157.22.0/24.
Removing Route Dampening from a Neighbor's Routes Suppressed Due to
Aggregation
You can selectively unsuppress more-specific routes that have been suppressed due to aggregation, and allow the
routes to be advertised to a specific neighbor or peer group.
December 2005 © Foundry Networks, Inc. 21 - 61