Thursday, 27 August 2009

Passing the CCNA: My experience

This blog explains why I've been quiet for a few weeks...

I did the CCNA exam back in 2002, but by the time it expired in 2005, I wasn't doing anything specifically with networks so didn't bother re-certifying. A couple of months ago I thought it would be a good cert to pick-up again, so decided to dive in and do some self-study.

The original CCNA was the entry level Cisco exam, but in the last few years this has been replaced by the CCENT. The CCNA is a lot harder than it used to be with many new subjects and a deeper level of understanding required. You can either approach the certification using two tests (ICND1 which gives you the CCENT and ICND2 which results in the CCNA) or by using one combined exam. I opted for the one exam.

I bought the latest version of Todd Lammle's CCNA Study Guide and started studying one chapter per night (there are 14 chapters, but real life meant that it took more than 14 days). I also spent weekends studying as well. The book is generally very good, although I found that because I wasn't replicating the example network used in the book, some sections required me to visualise and absorb what was being shown without any hands on experience. I would highlight the chapter on understanding subnet masks though; probably the best way to learn subnetting I can imagine.

I also purchased the Cisco Press Official Exam Certification Library by Wendell Odom. I planned on using this to get another perspective on the material and started reading bits of this book to clarify areas after I had completed the Lammle book. In comparison with the Lammle book, Odom is a lot more detailed (some might say dry but I enjoyed it). I discovered that, for my learning style, the Odom book helped me more. I found the thorough details showing how something works, step by step, to be very useful.

I managed to borrow some old Cisco kit from work and a laptop from work. This consisted on two 2600 routers, two Catalyst 2900XL switches and a 1700 series router. I didn't have the proper serial cable so couldn't do any WAN activities, but did use the kit to validate my understanding of VLANs, VTP and IOS commands (including the boot process, wiping configs etc).

The final part of my studying involved the CDs provided with the books. The test questions with the Lammle book were pretty straightforward and I was able to get 80%+ in the mock exams without too much trouble.

The Odom book was a completely different matter. These questions are hard. Really hard. I initially found that the time limit in the exam was running out on me, and that I was struggling to get my head around some of the questions at all. Whereas in the original exam, you might be asked a question like:

Given an IP address of, what is the subnet address, first host, last host and broadcast address?

Now the exam was asking you to look at a network topology diagram with maybe six of these networks and you have to choose a spare subnet range. In other words, you have to do six times the work for single question.

Although I managed to get faster at the questions, and especially enjoyed the simulator questions (where you have to log into simulators of routers and either fix the configuration or use the show commands to identify certain things), I never managed to achieve a pass mark.

I resigned myself to the fact that I wasn't going to pass this exam and instead decided to treat it as an educational experience to work out how difficult it was going to be.

Now the actual exam itself is covered by NDA, so it would be improper of me to comment on the specifics. There were simulations but they weren't too difficult and the majority of the questions were more of the difficulty level found in the Lammle book vs the Odom book.

For those looking at getting the CCNA, I would strongly recommend the two books I used. If you can master the Lammle book, you'll probably do okay. If you can master the Odom book, you'll walk the exam with one arm tied behind your back.

On a personal note, I actually enjoyed the process of learning. I find the networking concepts fascinating, and might even look at doing another cert at some point (we all need a hobby, right?). Not sure T will be too happy about losing me for another month.

At least now I can chillax a bit and enjoy what remains of summer... :-)

Sunday, 9 August 2009

Essential Firefox add-ons

Thought I'd better tidy up my Firefox add-ons as I appear to have accumulated a number that either served a specific purpose and are now redundant (Web Developer) or simply aren't needed (FlagFox).

The list of Add-ons I'm currently using on my Linux workstation are:

  • Blocksite (essential if you want to block Facebook Beacon)
  • Evernote Web Clipper
  • Flashblock (enable Flash objects on a per-site basis)
  • Gmail Manager (to alert when I get new Gmails)
  • TwitterFox (how I generally track Twitter)
  • Wikipedia Lookup Extension (highlight word, right click, search in Wikipedia)
  • Xmarks (Bookmark sync)
I don't use AdBlock because I'm generally not bothered by the adverts on sites I visit regularly, and I'm not enough of a Firefox hacker to want to bother with Greasemonkey. Perhaps something to manage passwords better would be good though.

Am I missing anything essential?

Thursday, 6 August 2009

Another blog worth reading...

My colleague, "JW", has joined the blogosphere and will be documenting some of the adventures he has in the world of Tech. It's off to a good start with a decent write-up of some of the challenges we experienced when we installed VMware and XenServer on a Sun X6240 blade module.

Check it out at Ting Ting Tech.