On Fri, Jul 12, 2024 at 02:30:10AM +0000, Ponikierski, Grzegorz via Bird-users wrote: > Hello all! > > How many standard communities, extended communities and large > communities, user can apply on a route using Bird? BGP UPDATE message has > finite size so I guess that there must be a limit somewhere.
Hello There is no specific limit on communities, just a limit on overall BGP attribute length on export, which is 1 kB less than BGP message size (there is 1 kB reserved for prefixes). So with regular BGP messages, there can be at most 3 kB of attributes, which is ~768 standard, ~384 extended, or ~256 large communities. In fact, it is a slightly less due to attribute framing and presence of other attributes than communities. -- Elen sila lumenn' omentielvo Ondrej 'Santiago' Zajicek (email: santi...@crfreenet.org) "To err is human -- to blame it on a computer is even more so."
