Information Technology Reference
In-Depth Information
Flexible Local Preference Route Map Configuration (Continued)
Example 9-6
!
route-map cust_inbound permit 20
match community 11
set community 100:3000 additive
set local-preference 90
!
route-map cust_inbound permit 30
match community 12
set community 100:3000 additive
set local-preference 110
!
route-map cust_inbound permit 40
match community 13
set community 100:3000 additive
set local-preference 120
!
route-map cust_inbound permit 50
set community 100:3000 additive
set local-preference 100
!
ip community-list 10 permit 100:80
ip community-list 10 deny
!
ip community-list 11 permit 100:90
ip community-list 11 deny
!
ip community-list 12 permit 100:110
ip community-list 12 deny
!
ip community-list 13 permit 100:120
ip community-list 13 deny
!
These route maps are an extension of the route maps defined in Example 9-4 on prefix
origin communities.
Controlling Upstream Prefix Advertisement
The ability to affect the ISP's advertisement of customer prefixes to upstream peers is
another policy aspect that can be made flexible through community usage. Two levels of
granularity are often defined. The first level requests suppression of advertisement to
upstream peers based on the peer type, transit, peering, or customer. The community
scheme for this is shown in Table 9-3.
