[Babel-users] How to redistribute only a specific Network addresses

[Juliusz Chroboczek]

> I'm using babel on some devices connected to several networks and I want them to
> share with each other the informations regarding only one of those networks (the
> one who connects them).  For example, a node A has a interface 1 conected to the
> network 20.0.0.0/8 and a interface 2 connected to a network 40.X.Y.0/24. With
> several nodes I want to form a mesh network so that they can communicate each
> other by the 20.0.0.0/8 network but I don't want them to know the 40.0.0.0/8
> networks of the other nodes.

> How can I configure babel to do it? 

If you want network 20 to be a pure mesh (only /32 routes
distributed), then do

  redistribute local ip 20.0.0.0/8 allow
  redistribute local deny

If network 20 also has some shorter prefixes, you'll probably need to
say something like

  redistribute ip 20.0.0.0/8 proto 3 allow

for the right value of 3 (use "ip route show" to check the proto
number of the routes you want to redistribute).

Note that lack of a "proto" qualifier means "proto anything-except-3".

-- Juliusz