CCIE Training

Followup to "Have you seen my Router ID?", dissecting a task from a strategy / knowledge point of view.

Challenge post on OSPF configuration.

The feature we are going to talk about today may look a bit convoluted, but it demonstrates core OSPF behavior: combining link-state and distance-vector behaviors. The command capability transit was introduced in IOS 12.3T and is on by default. However, the description is rather confusing and does not explain the underlying mechanics. We are going [...]

We have added a lesson to the 10-day ATCOD on EIGRP for IPv6. This is a key CCIE R/S Version 4.x topic. Enjoy!

One of the most popular series on this blog site is the Redistribution series by Petr Lapukhov. I wanted to share a document that helped one of my recent, incredibly dedicated, 12 Day Bootcamp students, Sean Coetzee. Thanks for sharing Sean! Redistributing Routing Protocols http://www.cisco.com/application/pdf/paws/8606/redist.pdf

If you are interested in Part 1 of this blog series – click here. Question 2 of 105 Given the topology and configurations shown in the exhibits. Which devices will receive EIGRP Query packets if R1 loses its route information for the 10.10.10.0/24 prefix? a) None of the devices b) R2, R3, R4, R5, R6, R7 c) R2, R3, R6, [...]

Intro There was a lot of blogging related to OSPF topics recently. In this post, I would like to clarify some common misunderstandings that many people have about OSPF route filtering. I have seen so many folks (some of them really experienced persons!) incorrectly understanding the underlying behavior so it’s about time to make this clear. [...]

The final in a series of blog posts examines the Totally Not-So-Stubby Area.

EIGRP is based on the concept of diffusing computations. When something changes in network topology, the routers that detect a loss of network prefix will send out EIGRP QUERY messages that propagate in circular waves similar to the ripples on water surface. Every queried router will in turn query its neighbors and so on, [...]

Here we look at the Not-So-Stubby area in OSPF.