Aha! I have found the answer to my own question about why the summary from R2 isn't used even if there is no null0 route. Answer - because the RFC says it shouldn't be ;-) Specifically, RFC2328, 16.2(3), when considering summary LSAs to build the routing table... "If it is a Type 3 summary-LSA, and the collection of destinations described by the summary-LSA equals one of the router's configured area address ranges (see Section 3.5), and the particular area address range is active, then the summary-LSA should be ignored. "Active" means that there are one or more reachable (by intra-area paths) networks contained in the area range."
When all else fails, RTFM (or RTFRFC in this case). All those people who knew this all along and were wondering what on earth I was confused about can now shake their heads and wonder at my ignorance ;-) This has been a most enlightening thread. JMcL ----- Forwarded by Jenny Mcleod/NSO/CSDA on 08/04/2002 03:29 pm ----- "[EMAIL PROTECTED]" Adding a point to point link between ABR's would enhance the resiliency >between the two and tend to protect against Area partitioning. Depending >on the capabilities of the backbone routers, letting more specifics into >the backbone might be helpful as well as it would deliver more optimal >routing and also help solve this problem. > >Shorter answer is, ya, thats a good idea in my opinion :) > >Pete > > [snipped] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=40790&t=40269 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
