Hi all, I've noticed that BIRD doesn't advertise the best external route to iBGP peers (as it "should" according to RFC 1771) if there is already an iBGP route for the same destination. I realize this is a point where most BGP implementations deviate from the standard, although many of them offer knobs to enable best external route propagation[1][2]. Still, this is a useful behaviour, especially in active-backup setups where backup paths are completely hidden from the rest of the AS. In essence, it looks as if BIRD can do this with sorted tables and the secondary BGP option, but unfortunately sorted tables are incompatible with iBGP's multihop operation due to the recursive gateway calculation strategy. Another option is of course add-paths, but then BIRD advertises all received paths, leading to a larger memory consumption than necessary. So, in case I'm missing something, is there another way to achieve best external route propagation over iBGP? Regards, Apollon [1] http://www.juniper.net/documentation/en_US/junos13.2/topics/example/policy-a... [2] http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iproute_bgp/configuration/x...