Avaya 1000 Series Configuration Manual page 316

Configuring BGP Features
Avaya1/configure/router/bgp 100> no aggregate_address 18.1.0.0
255.255.248.0 summary_only as_set
This would have remove the aggregate announcement and send all the more specific routes.
Look at Avaya2's bgp table, it has all the routes except the 18.1.0.0/21 route.
Avaya2> show ip bgp table
BGP route table, local router ID is 100.1.1.3 Status codes: * valid, > best, i -
internal Origin codes: i - IGP, e - EGP, ? - incomplete
Network
18.1.1.0/24
18.1.2.0/24
18.1.3.0/24
18.1.4.0/24
18.1.5.0/24
18.1.6.0/24
18.1.7.0/24
To apply a suppress map, select a block of routes that needs to be suppressed. This can be
done using IP_ACCESS_LISTS. Create an ip access list that blocks a set of routes in the
18.1.1.0 to 18.1.7.0 range.
Avaya1/configure> policy ip_access_list 1 1 permit network 18.1.0.0
netmask 0.0.3.0 mask 255.255.255.0 maskmask 0.0.0.0
The above access list would permit routes 18.1.1.0, 18.1.2.0, and 18.1.3.0 and deny everything
else.
Configure a route_map with the name ToAvaya2 to match the ip access list in it.
Avaya1/configure> policy route_map ToAvaya2 1 permit
Avaya1/configure/policy/route_map ToAvaya2 1> match ip ip_address 1
Avaya1/configure/policy/route_map ToAvaya2 1> exit
The above route map would allow routes by matching them with the ip access list 1. All other
routes would get denied. Suppress map applies a route map to to get the routes that needs to
be suppressed.
Apply the route map ToAvaya2 in the suppress map command to our previous aggregate
address command.
Avaya1/configure/router/bgp 100> aggregate_address 18.1.0.0
255.255.248.0 suppress_map ToAvaya2
The above command would apply a route-map on the more specific routes and permit what
matches the ip access list 1. Then the routes that were permitted by the route map are
316 Avaya Secure Router 1000 Series Configuration Guide
Orig Next Hop Next Hop
20.1.1.1 20.1.1.1
20.1.1.1 20.1.1.1
20.1.1.1 20.1.1.1
20.1.1.1 20.1.1.1
20.1.1.1 20.1.1.1
20.1.1.1 20.1.1.1
20.1.1.1 20.1.1.1
Metric LocPrf Path
100 200 ?
100 200 ?
100 200 ?
100 200 ?
100 200 ?
100 200 ?
100 200 ?
December 2010