[c-nsp] match multiple communities in route-map

Andy BIERLAIR andy.bierlair at root.lu
Tue Mar 24 11:28:26 EDT 2009

I have read that multiple match lines in a route-map are treated with AND

But this scenario here does not do AND, but OR:

route-map IX-TEST-OUT permit 10
  match community PREPEND-1-PEERING
  match community PEERING-OUT
  set as-path prepend 65001

route-map IX-TEST-OUT permit 20
  match community PREPEND-2-PEERING
  match community PEERING-OUT
  set as-path prepend 65001 65001

route-map IX-TEST-OUT permit 30
  match community PEERING-OUT

What I am trying to do is this:

1) Every customer who is sending me prefixes gets a community tag via
inbound route-map. Every prefix gets injected into community PEERING-OUT.

PEERING-OUT has all the prefixes I want to announce to my peers (not
transits!) on a public Internet Exchange

2) The customer can send a certain number of communities to us in order to
manipulate ingress traffic towards his ASN. For instance community list
PREPEND-x-PEERING has all the prefixes that customers want to apply
prepending to.

Prepending Communities are:

64600:X - Prepend X times to Transit (x = 0 - 4)
64700:X - Prepend X times to Peer (x = 0 - 4)

In order to announce all my prefixes correctly to my peers, I need to match
multiple communities - or find a different solution.

In my scenario above all my peers will get ALL my prefixes with 1x
prepending of 65001, and not just those that match PREPEND-1-PEERING.

I also tried the "continue" statement in route-maps, but this didn't seem to
help either.

What is wrong with this scenario?



More information about the cisco-nsp mailing list