Ondrej Zajicek <santiago@crfreenet.org> wrote on 2010/12/21 00:59:18:
On Fri, Dec 17, 2010 at 02:36:50PM +0100, Joakim Tjernlund wrote:
Question:
in calc_next_hop() does this* match 16.1.1 para 5. ...the parent vertex is a network that directly connects the calculating router to the destination router. The list of next hops is then determined by examining the destination's router-LSA...
..
Should not OSPF add a nexthop for ALL links that point back: ...For each link in the router-LSA that points back to the parent network, the link's Link Data field provides the IP address of a next hop router. The outgoing interface to use can then be derived from the next hop IP address (or it can be inherited from the parent network).
Not sure what you exactly mean. For a common scenario when there are two (or more) parallel links between two routers, multihop is used, because calc_next_hop() is called each time for each link and the results are merged.
Not this one.
Or if you means case like: Router A having two interfaces (with IP1 and IP2) connected to the same network N, router B also connected to network N may use multihop to IP1 and IP2 for routes that goes through router A. It is true that in that case BIRD does not use multihop (and there are some other corner cases, where multihop also is not used although it could be).
yes, this one. Seems like multihop only works for ptp links then ? perhaps not a big deal? I would think users of ECMP would like this case to work too though. Jocke