Thoughts

Well, at least some of it. Adjacencies and how IS’s update other IS’s is the thing that nobody can give me an answer to. According to all the material IS’s maintain adjacencies to all others, but still elect a DIS.

When doing the labs on this, the only thing I can see the DIS doing is sending out CSNP’s (Complete Sequence Network PDU’s). The DIS is also sending out hello’s every 3.3 seconds by default. However, LSP (Link State PDU’s (packets)) will get sent from every router that has something to say, directly to all other routers, not the DIS. So its role is somewhat different than a DR/BDR in OSPF.

Also, according to material, the DIS should send out a pseudonode-LSP on behalf of the broadcast medium. I havent seen this on labs either.

So yesterday, I started with all the lab exercises that has to do with EIGRP. I did the one in the self-study guide, and one (2.7.1) in the lab portfolio. I also started on 2.7.2.

So far, the labs in the labportfolio are far better written than the ones in the self-study guide. Today, I have snuck in a few practice scenarios regarding default route propagation.

3 ways to do it:

Number 1:
“ip route 0.0.0.0 0.0.0.0 <next-hop>” on advertising router.
“ip default-network <classful network to the default route>” on advertising router.

Number 2:
“ip  route 0.0.0.0 0.0.0.0 <next-hop>” on advertising router.
“redistribute static” on advertising router.

Number 3:
“ip route 0.0.0.0 <next-hop>” on advertising router.
“ip summary-address eigrp <AS> 0.0.0.0 0.0.0.0″ on advertising router.

This is just plain stupid in my opinion.

On another note, yesterday Ciscokits confirmed my order. I will be receiving:

1x 2611XM (100mbps router)
1x 2509 Access server
4x Back to Back cables (DB60)
2x Wic-1T cards
1x nm 4A/S card (Used for Frame Relay switch).
Memory upgrade for my current 3640 and 2611 (for 3640 to run 12.4).
Octal cable (to connect to all the equipment.

That means I will have:

1x 3640 with nm 4A/S
1x 2611 with 1 WIC-1T
1x 2611XM with 1 WIC-1T
1x 2509 Access server
2x 2950 switches
1x 2924 switch
+ a few other routers (which Mølgaard Netcom, was kind enough to lend me), I need to figure out.

Anyways, back to see if I can get some work done.

Alright, I am done with reading about EIGRP. I am now skimming through the chapter, and taking notes. I have an okay understanding of how EIGRP works, and I am looking forward to the labs to nail out unknowns.

I am not 100% convinced about taking notes, or rather doing it in the order im doing (reading first, then skimming and taking notes, then going to the lab).

However, when Im done with note-taking i can cross out the “Explain the functions and operations of EIGRP” in the exam blueprint

Anyways, goal for today is to get note taking down, and maybe even skim over some labs.

Today, I am continuing reading about EIGRP.

My goal for today is to get at least 40 pages of EIGRP reading done. Lots of nitty gritty details such as unequal-load balancing and route authentication.

To understand and process the material, 10 pages takes up 30 minutes of reading time. This includes reading the material, looking at the topologies being presented and thinking it through (in case of metrics and bandwidth calculate a bit to see where the authors are getting at).

I will update this post later in the day to track my progress.

update:

Okay, so I managed to read close to 40 pages of EIGRP today. Lots of information. Among these are:

• Authentication
• EIGRP on WAN links (use of bandwidth + percentage of bandwidth usage on link)
• Dual workings (Diffuse Update ALgorithm)
• Manual route summarization
• Beginning of EIGRP stub and EIGRP hub
• SIA (Stuck-In-Active) (EIGRP never getting a reply to a query packet)
• Graceful shutdown

All in all, a very good day in the BSCI study program.

Chapter 3, EIGRP.

Started reading about the inner workings of EIGRP today. EIGRP is an improved distance vector protocol provided by Cisco themselves. It is an improved distance vector protocol, because it passes updates directly to its neighbours. It is more advanced than traditional distance vector protocols, because it supports VLSM and it does not use periodic updates. It uses hello packets like link-state protocols.

1st reading done includes:

• EIGRP packet types.
• DUAL selection + selection examples.
• Neighbour establishments.
• Successor(s) + feasible Successor(s).
• Advertised distance + feasible distance.
• Metric calculations.

Okay. I will try and document some information regarding my study to attain the BSCI (Building Scalable Cisco Internetworks) exam.

This is by many considered the hardest exam on the CCNP track (1 of 4 exams). I will tackle this one first, and then continue forward to the other exams knowing they will be easier.

At the moment, I am on the second chapter of the self-study guide from cisco press. There is alot of lab work involved in the CCNP track with topology thats more complex than what I saw on the CCNA level. Also, I have to test out alot more concepts in the lab to make sure I understand it. This might just be me, I dont know.

Anyways. Been doing labs about Classless routing protocols, and how they send and receive information.

I got a good link from a guy on techexams.net, its from Cisco’s website, which I really need to use as a tool to fill in the gaps in knowledge, here it is:

Behavior of RIP and IGRP.

Also, Dynamips/Dynagen is a blessing. I am probably going to order some real life hardware no matter what, but with dynamips, you can have a full featured lab on your computer. Its awesome. Only thing I take issue with, is that multiple routers are not as synchronized as real routers. If I run a “debug ip packet” on one router, and ping it from another router, it lists all the pings sequentially on one router like it would on real hardware, but on the receiving router, it doesnt list a debug line per ping, but lists them in bulk or at least not at the same time as I would expect.

Also, there are alot of exceptions and intracacies here. For example, it turns out that the “ip classless” command will be completely ignored when running OSPF or IS-IS.

Okay, back off to work, hope to get some reading done this afternoon.

Okay, so its been a while since my last post.

Been having some issues to deal with, which has taken quite alot of energy.

I am going for the CCNP, starting with the BSCI exam. Ive got the books for it, and started studying. There’s alot of detailed information, and lots of labs to do. Chapter 2 is 40 pages long, and its taken me two days to reach the end of the information in the book, now im starting the labs in the end of the chapter

I am just going to hang in there, and do everything I can. What really bothers me, is that I dont get it right away, and need to try it out multiple times with multiple scenarios.