On Thu, Nov 26, 2020 at 08:02:38PM +0000, Kenth Eriksson wrote:

If I configure an OSPF interface as a stub interface, why does it appear twice the routing table? E.g. setting interface lo as stub interface results in the following;

10.210.137.78/32 unicast [direct1 15:59:09.550] * (255) dev lo unicast [ospfv2_1 20:47:56.864] I (145/0) [10.210.137.78] dev lo

The source OSPF-I misleads me in thinking that it was learned from the OSPF area.

Hi OSPF protocol in BIRD offers routes to all destinations in OSPF domain, including ones that are currently best-reachable by a direct route. Note that even if a prefix is a local stub/direct network, there may be (in principle) an indirect route with lower OSPF cost, in that case OSPF would supply that, while the Direct protocol (direct1) would still supply the direct route. It is also useful because direct routes from OSPF protocol have attached OSPF metric, so in conjunction with BGP recursive next hop processing proper IGP metric is used (if the route is not shadowed by route from the Direct protocol). The OSPF-I just means the route is intra-area route (which is true). In general, having direct routes from Direct protocol is probably not much useful, if you already have one from OSPF. -- Elen sila lumenn' omentielvo Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."