Hi guys, recently I asked the question about what has priority in which IOS version, regarding external OSPF routes. Will we prefer 'N' or 'E' routes, if they are of the same type and the same metric. There was a dispute about which RFC some IOSes conform to etc... Tyson said that the good guess is 12.4(15)T so I decided to try this IOS and see what happens.
This is all on dynamips, so maybe it influenced some peculiar events, but somehow I doubt it. The topology is like this: - R2 is the "hub" where everybody connects, there are three areas 0,1 and 3 - R1 is in standard area 1, redistributing 1.1.1.1 network - R3 is in NSSA area 3, redistributing also 1.1.1.1 network - R4 is in area 0, on the "other side" of R2 when looking from the point of R1 and R3 So, R2 sees both paths to 1.1.1.1, one through R1 and the other through R3 (nssa). R4 sees converted LSA-7 to LSA-5. 1. R2 preferred 'E' route over 'N' route. One dilemma solved, with this IOS at least. Of course, when we have 'N1' route and 'E2' route, 'N1' is preferred. 2. I noticed incosistency when it comes to forward address field. I know it should contain the IP address of the ASBR. But sometimes I get the IP of the R3 (ASBR) LAN interface connecting R2 and R3, and sometimes I get the loopback interface IP on the ASBR. I can't catch why it is changing and when. Anybody has the idea? Why would OSPF ever put loopback IP in there? Best Regards, Bojan Zivancevic Network Engineer ----
_______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
