I am doing alot of technology focused labs, and I always learn something new, which is really good. For example, I was studying the effects of autosummarization with RIP and EIGRP. A few things cropped up.
RIP will autosummarize routes it receives from other neighbors, where as EIGRP will only summarize those, if it has a locally connected network of the same major net, and it is included in a network statement.
Also, if both EIGRP and RIP receives a prefix from two different “directions”, it will send out a summary to both, since it was received from the other “end” so to speak. This is not in violation of split horizon since it technically wasnt learned from either direction.
With RIP and EIGRP, remember, autosummarization will only take place over a different major network boundary!
Also, been playing around with OSPF type 5 routes at work, for some reason, I cant get all routes to appear the way I want them to. I even labbed up the individual routes the same way as they are in real life, and in the lab they behave the way I want them to. Odd behavior, besides I cant find any information on this exact problem.
Good news though, this morning I checked my feeds and found out IPexpert had released a free tool to help you study for the open ended questions for the lab exam, you can get it here:
Learned a new usefull command when I was reading through the EIGRP section in the exam guide: “sh ip eigrp topology all-links”, I am used to the “sh ip eigrp topology” command, which lists successors and feassible sucessors, but this command displays all link learned by the EIGRP router.
Frame-relay and its peculiar Non-Broadcast is really messing up my head. Two ways t deal with NBMA environments (when you cant use point-to-point or point-to-multipoint):
1) Make sure that “sh frame-relay map” has a broadcast flag set to the neighbor, this happens either via inverse-arp or through a frame-relay map ip command with the broadcast option set. Then change the OSPF network type to broadcast: “ip ospf network broadcast”.
2) Make sure the neighbor is reachable, again via inverse arp or static frame-relay map command, then go into the router OSPF process and define the neighbor manually: “neighbor ”.
Remember both of these option will want to select a DR and BDR, so tweak the priorities to make sure the hub becomes the DR.
Ok, off to play around with some more frame-relay types.