But this filter applies in the antenna that advertise the route. 10.20.2.2 and 10.20.2.36 advertise 10.0.0.0/8 10.20.2.162 and 10.20.3.1 links with 10.20.2.2 and i want that 10.20.2.162 uses 10.20.2.36 (not direct link) for 10.0.0.0/8 not 10.20.2.2 and 10.20.3.1 uses 10.20.2.2 So i need to modify in 10.20.2.162 and 10.20.3.1 the 10.0.0.0/8 gateway Is this possible with babel? Thanks Oriol El El jue, 12 ene 2023 a las 16:11, Juliusz Chroboczek <jch@irif.fr> escribió:
We have a series of wireless antennas deployed in mesh with the babel protocol using bird. Two of those antennas advertise the route 10.0.0.0/8. The rest of the antennas choose one of the two outputs depending on
the
babel protocol. How can I force it to go out through one or the other exit?
You cannot force it, but you can strongly discourage one of the two nodes. Say something like this:
filter babel_discourage { if babel_metric < 1024 then babel_metric = 1024; accept "ok"; };
protocol babel { ... ipv4 { export filter babel_discourage; }; ipv6 { export filter babel_discourage; }; };
You should not do the opposite: a node can safely increase the metric it announces, thus discouraging its use by other nodes, but it should not decrease its metric artificially, since that might defeat Babel's loop avoidance.
-- Juliusz