Route-Map - Allied Telesis SwitchBlade x908 Series Software Reference Manual

BGP Configuration

Route-Map

Use route-maps to filter incoming updates from a BGP peer. In this example, a prefix-list
list1 on Peer 1 is configured to deny entry of any routes with the IP address 1.1.1.0/M
(M = 26,27,28). To test the filter, Peer 2 is configured to generate network addresses
1.1.1.0/27 and 1.1.2.0/24. To verify, use the show ip bgp command on Peer 1; it
displays Peer 1 receiving updates from only 1.1.2.0/24.
Peer 1
awplus#configure terminal
awplus(config)#ip prefix-list
prefixlist1 seq 5 deny 1.1.1.0/24 ge 26
le 28
awplus(config)#ip prefix-list
prefixlist1 seq 10 permit any
awplus(config)#route-map routemap1
permit 1
awplus(config-route-map)#match ip
address prefix-list prefixlist1
awplus(config-route-map)#exit
awplus(config)#router bgp 10
awplus(config-router)#neighbor
192.168.10.11 remote-as 11
awplus(config-router)#neighbor
192.168.10.11 route-map routemap1 in
37.4
AS10
192.168.10.10
Peer 1
Enter the Configure mode.
Create the prefix-list named prefixlist1 as shown
opposite. prefixlist1 contains two entries. The first
entry with a deny action is to not match any routes in the
1.1.1.0/24 range that have prefix lengths from 26 to 28
(inclusive). The second entry allows all other routes.
Also note the sequence number (seq 5 seq 10) in the
prefix-list specifies the sequence for each entry.
Enter the route-map mode to set the match operation.
Set the match criteria. This match criterion on this route-
map entry is to match the incoming route updates against
the prefix-list prefixlist1. If a route matches the
permit criteria of the prefix-list prefixlist1, then
packets are permitted by the route-map, since this route-
map entry has a permit action. Because this is the only
entry route-map, all routes that are not permitted by this
entry route-map will be dropped.
Exit the Route-map mode and return to Configure
mode.
Define the routing process. The number 10 specifies the AS
number of R1.
Define BGP neighbors. 192.168.10.11 is the IP address
of the neighbor (Peer 2) and 11 is the neighbor's AS
number.
The route-map is now applied as the filter for route updates
that are received from the neighbor 192.168.10.11.
Routes are accepted from the neighbor 192.168.10.11
if they match the permit criteria of route-map routemap1.
Software Reference for SwitchBlade® x908, x900 and x600 Series Switches
TM
AlliedWare Plus Operating System - Software Version 5.3.1
AS11
192.168.10.11
Peer 2
C613-50007-01 REV B
bgp_3