Brocade Multi-Service IronWare Routing Configuration Guide (Supporting R05.6.00) - Manual (Page 81)

Multi-Service IronWare Routing Configuration Guide 53
53-1003033-02
Configuring BGP4 neighbors
Removing route dampening from suppressed routes
You can selectively unsuppress specific routes that have been suppressed due to aggregation, and
allow these routes to be advertised to a specific neighbor or peer group.
In this example, the aggregate-address command configures an aggregate address of 10.1.0.0
255.255.0.0. and the summary-only parameter prevents the device from advertising more specific
routes contained within the aggregate route.
Entering a show ip bgp route command for the aggregate address 10.1.0.0/16 shows that the
more specific routes aggregated into 10.1.0.0/16 have been suppressed. In this case, the route to
10.1.44.0/24 has been suppressed. If you enter this command, the display shows that the route is
not being advertised to the BGP4 neighbors.
To override the summary-only parameter and allow a specific route to be advertised to a neighbor,
enter commands such as the following:
The ip prefix-list command configures an IP prefix list for network 10.1.44.0/24, which is the route
you want to unsuppress. The next two commands configure a route map that uses the prefix list as
input. The neighbor command enables the device to advertise the routes specified in the route
map to neighbor 10.1.0.2. The clear command performs a soft reset of the session with the
neighbor so that the device can advertise the unsuppressed route.
Syntax: [no] neighbor ip-addr | peer-group-name unsuppress-map map-name
The show ip bgp route command verifies that the route has been unsuppressed.
Brocade(config-bgp)# aggregate-address 10.1.0.0 255.255.0.0 summary-only
Brocade(config-bgp)# show ip bgp route 10.1.0.0/16 longer
Number of BGP Routes matching display condition : 2
Status A:AGGREGATE B:BEST b:NOT-INSTALLED-BEST C:CONFED_EBGP D:DAMPED
E:EBGP H:HISTORY I:IBGP L:LOCAL M:MULTIPATH S:SUPPRESSED F:FILTERED
Prefix Next Hop Metric LocPrf Weight Status
1 10.1.0.0/16 0.0.0.0 101 32768 BAL
AS_PATH:
2 10.1.44.0/24 10.2.0.1 1 101 32768 BLS
AS_PATH:
Brocade(config-bgp)# show ip bgp route 10.1.44.0/24
Number of BGP Routes matching display condition : 1
Status A:AGGREGATE B:BEST b:NOT-INSTALLED-BEST C:CONFED_EBGP D:DAMPED
E:EBGP H:HISTORY I:IBGP L:LOCAL M:MULTIPATH S:SUPPRESSED F:FILTERED
Prefix Next Hop Metric LocPrf Weight Status
1 10.1.44.0/24 10.2.0.1 1 101 32768 BLS
AS_PATH:
Route is not advertised to any peers
Brocade(config)# ip prefix-list Unsuppress1 permit 10.1.44.0/24
Brocade(config)# route-map RouteMap1 permit 1
Brocade(config-routemap RouteMap1)# exit
Brocade(config)# router bgp
Brocade(config-bgp)# neighbor 10.1.0.2 unsuppress-map RouteMap1
Brocade(config-bgp)# clear ip bgp neighbor 10.1.0.2 soft-out