Re: OSPF anycast prefix being filtered

31 Mar 2015


      On 31/03/2015 06:41 μμ, Patrik Lundin wrote:
...
Hello,
I am trying to use BIRD for anycasting a /32 prefix via OSPF and I am
not able to get the announcement to work.
My idea is to have the server use the normal default gw for routing
packets. Because of this I see no reason for importing routes from
OSPF into the kernel routing table, I am only interested in exporting
the anycast address that is configured on the loopback interface.
I configure a /32 prefix on the loopback interface like so:
===
# ip address add yyy.yyy.yyy.yyy/32 dev lo
===
My bird.conf looks like this:
===
router id xxx.xxx.xxx.xxx;
debug protocols all;
protocol device {}
protocol ospf {
    import none; # Default is import all
    export all;
    area 0.0.0.0 {
        interface "eth*" {
            authentication cryptographic;
            password "pass";
        };
        interface "lo" {};
    };
}
You need to enable direct protocol as well which will import routes
to the routing table of Bird, here is an example conf

define ANYCAST_NETWORKS =
   [
       10.252.12.0/24{32,32}

   ];
protocol direct direct1 {
    interface "lo";
        debug all;
        export none;
        import where net ~ ANYCAST_NETWORKS;
}


Cheers,
Pavlos

Re: OSPF anycast prefix being filtered

Pavlos Parissis