The next chapter I have to do the write-up on is Spanning Tree. Ugh. I already read it, and it was a bit of a beast. Lots of stuff I knew, but spanning-tree is one of those topics that I never quite learned as well as I should have. It was a handy thing to blame from time to time when there’d be a network outage, you know? “Oh, uh…a line went down and spanning-tree converged. That’s why we had the outage.” Which was most of the time bollocks, but if your boss bought and let you go back to figuring out what the heck happened, well then, hey! It’s a line that works even better if all your boss knows about spanning tree is from about 10 years ago – you can cover a lot of network burps with that excuse.
But in the real world, you have to really know and understand spanning-tree, especially if you’re in a dual-homed environment. ST impacts redundancy, packet forwarding, switch design, load-balancing, etc. It’s a very big deal, and while it’s easy to get ST right, it’s also easy to screw it up. And it’s even easier to overlook some of the new ST features (such RST) and/or extensions that Cisco has provided (the “-fast” stuff).
So, tomorrow I’ll go back through my ST chapter review, and then on Wednesday at least get Chapter 4 started.
Man, this is going to be a long-haul getting through this book doing it this way, but I feel it’s important. There’s 24 chapters in the book, plus appendices. If I keep going like this, I’ll be lucky to get through the book by April. But I’ll have learned a ton of stuff that I didn’t know, and solidified a lot of things I did know. I’m not sure how I’m going to retain it all unless I work a little faster, though. We’ll see. If I review via Boson test questions from time to time, that should help keep the information fresh. There’s just so much here, and the book has very little “fat”. Everything seems relevant and important, 3 chapters in at least.