Avaya 1000 Series Configuration Manual page 322

Configuring BGP Features
18.1.5.0/24
18.1.6.0/24
18.1.7.0/24
The above output shows that all routes that came from Avaya1 have the community value of
100 or 0:100 set. Apply a route-map INBOUND on Avaya2 to filter any routes that comes from
AS 200. Currently Avaya2 has got routes except 18.1.0.0/21 coming from AS 200.
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
18.1.0.0/21
18.1.5.0/24
18.1.6.0/24
18.1.7.0/24
By putting a filter to block routes from AS 200 we should see only 18.1.0.0/21 which comes
from 100. To do this, use as_path filter to deny routes that come from AS 200. Again INBOUND
route-maps are applied to neighbors directly and outbounds are applied to GROUPs.
Avaya2/configure> policy route_map From100 1 permit
Avaya2/configure/policy/route_map From100 1> match
as_path 1
Avaya2/configure/policy/route_map From100 1> exit
Avaya2/configure> policy as_path 1 1 deny ".* 200"
The above commands create a route_map named From100 with sequence number 1 to permit
anything that matches as_path list 1. We have two sequence numbers in as_path, 1 1 is to
deny anything from originates from AS200 and 1 2 is to permit others.
The route map needs to be applied INBOUND under neighbor 20.1.1.1 which is Avaya1.
Avaya2/configure/router/bgp 300> neighbor 20.1.1.1 100
Avaya2/configure/router/bgp 300/neighbor 20.1.1.1 100>
route_map From100 in
Avaya2/configure> show policy route_map
Avaya2/configure> show policy as_path
AS path access list 1
permit .* 200
permit .*
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
18.1.0.0/21
322 Avaya Secure Router 1000 Series Configuration Guide
20.1.1.1 20.1.1.1
20.1.1.1 20.1.1.1
20.1.1.1 20.1.1.1
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
Orig Next Hop Next Hop
20.1.1.1 20.1.1.1
100 200 ?
100 200 ?
100 200 ?
Metric LocPrf
Metric LocPrf Path
100 i
Path
100 i
100 200 ?
100 200 ?
100 200 ?
December 2010