Dear all, On Tue, Dec 12, 2017 at 06:47:44PM +0100, Pier Carlo Chiodi wrote:

while I was running some tests on BIRD 2.0.0 I've noticed that the handling of RFC8097 extended communities is different from 1.6.3.

Scenario: - AS10 announces a route to the route server; - the route server adds the (0x4300, 0, 1) ext community (RFC8097); - AS20 receives the route; - clients are always both on 1.6.3.

This is the filter I'm using:

filter from_client { bgp_ext_community.add((unknown 0x4300, 0, 1)); accept; }

The results I get follow:

- when 1.6.3 is used on the route server, BIRD treats the community strictly according to RFC4360:

If a route has a non-transitivity extended community, then before advertising the route across the Autonomous System boundary the community SHOULD be removed from the route.

Hmm... I think it is in everyone's best interest that non-transitive BGP extended communities are actually treated as non-transitive (like in 1.6.3). This prevents surprises.

- when 2.0.0 is used, the community is treated accordingly to draft-ietf-sidrops-route-server-rpki-light-02 and is propagated to the client.

Since I didn't find any reference to RFC8097/rpki-light on the web site, I was wondering if I missed something or if this is the expected behaviour.

Please note that draft-ietf-sidrops-route-server-rpki-light is still heavily in flux, and the authors indicated that they'd move towards using a transitive extended community and abandon the non-transitive extended communities in the current revision of the draft. Kind regards, Job

On Tue, Dec 12, 2017 at 06:47:44PM +0100, Pier Carlo Chiodi wrote:

Hello,

while I was running some tests on BIRD 2.0.0 I've noticed that the handling of RFC8097 extended communities is different from 1.6.3.

- when 1.6.3 is used on the route server, BIRD treats the community strictly according to RFC4360:

If a route has a non-transitivity extended community, then before advertising the route across the Autonomous System boundary the community SHOULD be removed from the route.

- when 2.0.0 is used, the community is treated accordingly to draft-ietf-sidrops-route-server-rpki-light-02 and is propagated to the client.

Hi Here is a patch that should fix it. -- Elen sila lumenn' omentielvo Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."