cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
2768
Views
0
Helpful
4
Replies

Prefix-list matching to set community

Cody Lo
Beginner
Beginner

I would like to know if the following configuration, the announced route "192.168.1.0/24" will have the community "123:200 123:999" or "123:200 123:600", or other combination of community attribute? Thank you!

ip prefix-list routes1 seq 5 permit 192.168.1.0/24

ip prefix-list routes2 seq 5 permit 192.168.1.0/24

ip prefix-list routes2 seq 10 permit 192.168.100.0/24

!

route-map COMMUNITY_TO_R1 permit 10

match ip address prefix-list routes1

set community 123:200 123:999

route-map COMMUNITY_TO_R1 permit 20

match ip address prefix-list routes2

set community 123:200 123:600

!

router bgp 40

no synchronization

bgp router-id 10.1.1.2

bgp log-neighbor-changes

network 192.168.1.0 mask 255.255.255.0

network 192.168.100.0 mask 255.255.255.0

neighbor 10.1.1.1 remote-as 123

neighbor 10.1.1.1 send-community

neighbor 10.1.1.1 route-map COMMUNITY_TO_R1 out

no auto-summary

1 Accepted Solution

Accepted Solutions

Cody,

That's correct. If you need it to match another one in a later sequence you could use the "continue" clause in the route-map.

ip prefix-list Test permit 192.168.1.0/24

ip prefix-list Test2 permit 192.168.1.0/24

ip prefix-list Test2 permit 192.168.2.0/24

route-map Testing permit 10

match ip address prefix Test

set community 123:999

continue

route-map Testing permit 20

match ip address prefix Test2

set metric 50

The above would set your community to 123:999 and it would set both 192.168.1.0/24 and 192.168.2.0/24 metrics to 50. If you didn't have the continue, it would only set the metric to 50 for the 192.168.2.0/24 subnet.

HTH,

John

Please rate helpful posts..

HTH, John *** Please rate all useful posts ***

View solution in original post

4 Replies 4

John Blakley
Advisor
Advisor

Cody,

It should be matching your first sequence in your route-map.

HTH,

John

HTH, John *** Please rate all useful posts ***

Ho John,

Thanks for the prompt reply.

Does that mean if a route appear in 2 different prefix list and match in the same route map it will only match and altered at "permit 10" but not "permit 20" ?

Thanks!

Cody

Cody,

That's correct. If you need it to match another one in a later sequence you could use the "continue" clause in the route-map.

ip prefix-list Test permit 192.168.1.0/24

ip prefix-list Test2 permit 192.168.1.0/24

ip prefix-list Test2 permit 192.168.2.0/24

route-map Testing permit 10

match ip address prefix Test

set community 123:999

continue

route-map Testing permit 20

match ip address prefix Test2

set metric 50

The above would set your community to 123:999 and it would set both 192.168.1.0/24 and 192.168.2.0/24 metrics to 50. If you didn't have the continue, it would only set the metric to 50 for the 192.168.2.0/24 subnet.

HTH,

John

Please rate helpful posts..

HTH, John *** Please rate all useful posts ***

Thank you John, having tested with 2 routers today and the result is like what you point out. Thanks.

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Recognize Your Peers