OSPF Summarization is done only on ABR and ASBR routers in your OSPF domain, and use two completely different commands, but what if a router is an ABR and an ASBR? For example, did you know that using the command "default-information originate ..." you are telling the router to create a Type 5 LSA to … Continue reading OSPF: Important details regarding Summarization and Default Routes for exam day, it’s a long but worthwhile read!
I pulled this topology from my older posts when I took a deep dive into the world of LSA's, how to read the Topology table like a laundry list and under stand it, and what type of routers did what. First I want to list links that are absolutely vital to read and understand for … Continue reading A collection of IMPORTANT links to review and know for exam day, then a quick overview of LSA Types / OSPF Router Types!
Only the NBMA and Ethernet segments will be used for quick demonstrations and clarity, unless R4 or R5 is needed for demonstration. Now the idea of a Prefix-List in comparison to an Access-List may be hard to follow, but I will try to explain it. An Access-List at its most specific (Extended) matches only on … Continue reading EIGRP: DEEP Dive into Prefix-List configurations, Access-list vs Prefix-list, using Prefix-Lists to Filter EIGRP routes with Distribute-Lists!