Brocade Communications Systems Layer 3 Routing Configuration ICX 6650 - Manual (Page 374)

356 Brocade ICX 6650 Layer 3 Routing Configuration Guide
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Route flap dampening configuration
The address-filter commands in this example configure two BGP4 address filters, for networks
10.157.22.0 and 10.157.23.0. 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 10.157.22.0, 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 10.157.23.0. 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.
To enable route flap dampening for a specific BGP4 neighbor, enter commands such as the
following.
Brocade(config)#router bgp
Brocade(config-bgp-router)#address-filter 9 permit 10.157.22.0 255.255.255.0
255.255.255.0 255.255.255.0
Brocade(config-bgp-router)#address-filter 10 permit 10.157.23.0 255.255.255.0
255.255.255.0 255.255.255.0
Brocade(config-bgp-router)#exit
Brocade(config)#route-map DAMPENING_MAP permit 9
Brocade(config-routemap DAMPENING_MAP)#match address-filters 9
Brocade(config-routemap DAMPENING_MAP)#set dampening 10 200 2500 40
Brocade(config-routemap DAMPENING_MAP)#exit
Brocade(config)#route-map DAMPENING_MAP permit 10
Brocade(config-routemap DAMPENING_MAP)#match address-filters 10
Brocade(config-routemap DAMPENING_MAP)#set dampening 20 200 2500 60
Brocade(config-routemap DAMPENING_MAP)#router bgp
Brocade(config-bgp-router)#dampening route-map DAMPENING_MAP