OSPF Stub Types

I spent this Christmas morning studying and configuring the 3 stub types, Stub Area, Totally Stubby Area, and NSSA (Not So Stubby Area). I'm not going to even ask who came up with those names but the material made since as long as you undertood how it effects the LSA type you receive in that particular area. I also ran into something I NEVER noticed so far in the past 8 months I've been learning about Cisco. If you have two directly connected serial interfaces, you CAN'T ping you're own serial IP address if the other side of the serial link is misconfigured in any way. I spent a better part of 30 minutes troubleshooting this problem and even blaming it on the GNS3 program itself until I did a little research. Even if your serial interface shows up/up, if you can't ping your serial IP it's a good chance there's a misconfiguration on either side of the point-to-point connection. MERRY CHRISTMAS!

OSPF Default Route Summarization

My lab studies today was kinda of all over the place. One of the labs I created was testing out connections to my PC's loopback and watching frames be put on the wire (with Wireshark) to my GNS3 lab. Well some how during the testing of this I lost DNS connectivity with my PC and I couldn't for the life of me figure it out. I didn't realize it was an issue with DNS until I tried connecting to google.com using it's IP address and worked but couldn't by using it's host name. After about an hour of t-shooting my own home network (including replacing a router-switch) a simpl reboot fixed all my issues. Troubleshooting 101 tip...reboot your computer first to see if this resolves your problems! Anyways after that fiasco, I finished my studying today about learning a little bit about the different stub types and configuring a multi-homed OSPF lab dealing with route summarization.

Chapter 5 Advanced OSPF Configuration

I began my studies on chapter 5 in the CCNP BSCI Study Guide book on OSPF this morning. I could tell immediatly that the level of depth ramped up and I'm positive it will remain this way from hear on out. The first 4 chapters seemed more like review to me and I was kind of worried I wasn't studying hard enough because I didn't seem to gain a deeper knowledge really of the material and understood most of the topics before I even read the chapters. This Chapter is really starting to show me why they can consider this a professional certification. I'm going to have to cut off all distractions during my study time (well besides my music) such as TV, Internet, etc. It actually worked out quite well this morning as I was able to read what I needed to and created a decent sized lab in about half the time it usually takes me. I learned about the many LSA types and when they are used today. I finished up today by creating a lab that shows the different LSA types sent based on the routers role. In this lab you'll see a couple of ABR's (Area Border Routers), an ASBR (Autonomous System Border Router), and internal routers in their respective areas.

CCNP Chapter 4 OSPF Lab

This morning I polished off the rest of chapter 4 by completing the end of chapter lab which wasn't to bad. I was able to barely finish as an issue arrived with a customers PIX being down. I will finish up the chapter review questions tonight and prepare to move on to the advance routing section this upcoming week. I also will start going over this network security design book an engineer was able to loan out. It's probably a good idea to double up on the security and CCNP studies, I think CCSP might be my next exam after CCNP of course. I also configured quite a bit of different labs concerning OSPF settings when running over a NBMA network last night and this morning. I'm sure I'll be coming back and brushing over a lot of this material again when it comes closer to test time.

Configuring Basic OSPF Routing

Today I spent the better part of my morning configuring two simple OSPF labs along with reviewing the different show and debug commands. It was mostly review but I did get a better understanding of how the OSPF process works by watching the debug commands take place on the routers them selves. I finished off today by studying about the different OSPF network types which are Broadcast, Point-to-Point, and NBMA (Non-Broadcast Multi Access) Networks. Tomorrow I learn about about the subtleties between the OSPF Adjancies along with learning and configuring a few different types of NBMA setups using Frame-Relay of course.

CCNP Basic OSPF Theory

Today I started my studying on OSPF in the CCNP BSCI Study Guide book. It was mainly just review of LSDB's, LSA's, and the packets that are used to get OSPF up and running. While most of it was CCNA review material the book did go in-depth regarding the packet types and their function. It also displayed interesting diagrams and analogies to help understand how OSPF builds its Link-State Database (LSDB). You can think of LSDB as a map you're looking at in the mall, and the mall it self being the OSPF network. There are multiple maps placed throughout the mall with the same information regarding where every store is located just the same as each router has the same LSDB in an OSPF network . The only difference between the maps in the mall is the "you are here" dot. The dot determines where you are in the mall and the best path to get to every store within that mall. OSPF functions very similar to this, each router uses the LSDB and it's location in the network to determine the best path to get to every other router within the OSPF network!

Tonight I will be finishing up a few more pages regarding OSPF theory and then tomorrow I hope to jump right into configurations, the fun stuff. The pic I added today shows the current topology of the entire global network, pretty wild stuff!

CCNP Chapter 3 EIGRP Lab

Today I finished up my EIGRP studies by compelting the end of chapter lab along with Q&A's. The lab wasn't to bad and I was able to get through it in a more timely matter than the last chapters lab due to not having to use 11 routers! By time I went through the lab I already knew how to set most things up due to going through all the examples so it really made the lab a breeze. Next week I begin my OSPF studies which I here is one of the most tested subjects on the exam.