OSPF Route summarization and redundancy

[joyride_us]

Hi,

If I have a LAN with 2 routers to access it. On each of those routers I use OSPF and route summarization (summarizing the LAN network addresses). How will redundancy work in case the active router looses the path to only one part of the LAN (Since the route is summarized : how does the sender know that it should go through the other router to get to that specific subnet) ?

Thank you

[Harold Ritter]

Make sure there is a link between the redundant routers and that this link is part of area for which you summarize. This way the routers will still have access to the LAN link via the other router in the event they loose direct connectivity.

Hope this helps,

[joyride_us]

Thank you. But for an external router trying to ping a host of the LAN. It will get both routes from each router, will select the best one. If that best router loses the path to 1 subnet on the LAN : this subnet is still advertised as part of the summarized address although it is not reachable any longer!

Are you saying that this "best" router will then reroute the packet to the other router ?

Thank you