Bgp Aggregate Route Examples; Configuring Bgp Confederations - Enterasys Security Router X-PeditionTM User Manual

Configuring BGP Route Maps
XSR(config-router)#neighbor 192.168.57.69 filter-list 3 out
XSR(config-router)#neighbor 192.168.57.69 filter-list 2 in
XSR(config-router)#exit
XSR(config)#ip as-path access-list 1 permit _102_
XSR(config)#ip as-path access-list 2 permit _200$
XSR(config)#ip as-path access-list 2 permit ^100$
XSR(config)#ip as-path access-list 3 deny _440$
XSR(config)#ip as-path access-list 3 permit .*

BGP Aggregate Route Examples

The following examples describe how to use aggregate routes in BGP either by redistributing an
aggregate route into BGP or by using the conditional aggregate routing feature.
In the next example, redistribute aggregate route 192.*.*.*:
XSR(config)#ip route 192.0.0.0 255.0.0.0 null 0
XSR(config)#router bgp 57
XSR(config-router)#redistribute static
In the following example, add an aggregate entry in the BGP routing table when at least one route
falls into the specified range. The XSR will advertise this route as originating from your AS and
has the atomic aggregate attribute set to indicate data may be lost. (By default, atomic aggregate is
set unless you use the as-set keyword in the
XSR(config)#router bgp 57
XSR(config-router)#aggregate-address 192.0.0.0 255.0.0.0
Next, you add an aggregate entry using similar rules as in the previous example, but the path
advertised for this route will be an AS_SET consisting of all elements within all paths being
summarized:
XSR(config)#router bgp 57
XSR(config-router)#aggregate-address 192.0.0.0 255.0.0.0 as-set
The last example adds an aggregate route for 192.*.*.* and suppresses advertisements of more
specific routes to all neighbors:
XSR(config)#router bgp 23
XSR(config-router)#aggregate-address 192.0.0.0 255.0.0.0 summary-only

Configuring BGP Confederations

The following example configures a confederation comprised of three internal AS's with AS
numbers 1, 2, and 3. To BGP speakers outside the confederation, the confederation appears to be a
standard AS with AS number 20 (set with the
In a BGP speaker in AS 1, mark the peers from AS's 2 and 3 as special EBGP peers with the
confederation peers
preference, next-hop and MED unchanged in updates. The router at 130.32.32.1 is a standard
EBGP speaker and the updates it gets from this peer will be similar to a standard EBGP update
from a peer in AS 20.
XSR(config)#router bgp 1
XSR(config-router)#bgp confederation identifier 20
XSR(config-router)#bgp confederation peers 2 3
XSR(config-router)#neighbor 192.168.57.5 remote-as 2
XSR(config-router)#neighbor 192.168.57.6 remote-as 3
6-24 Configuring the Border Gateway Protocol
aggregate-address
command. Peers 192.168.57.5 and 192.168.57.6 then will get the local-
command.)
bgp confederation identifier command).
bgp