Took my 15-year-old to his Blues School (guitar club) in Differdange. It wasn’t worth driving all the way home again and then all the way back to collect him, so I sat in the car for a couple of hours reading Wendell Odom’s CCIE Cert Guide. What a great book it is! When I was doing my CCNA back in 1999 I wasn’t such a fan of his CCNA Cert Guide. But the CCIE book is one of the most relevant, pithy, and challenging books I have on my bookshelf. No doubt the CCNA guide has also improved in the intervening 8 years.
I have the second edition of the CCIE book. Every time I dip into the book it comes up with a new way of looking at something I thought I knew. Today’s subjects were:
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Default routes and the various ways to introduce them into RIP, EIGRP, OSPF (pages 345 – 251) and BGP (pages 381 – 382). It goes into the differences in behavior between the different protocols with the different techniques. For example, whether the default route must already be in the table for default-information originate to work. (RIP: yes, but not if static; OSPF: yes, unless you have keyword always; EIGRP: not supported; BGP: yes for global version of the command, no for neighbor specific command)
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QoS MQC for marking. I didn’t realise that a class-map can have multiple match lines for the same attribute. For example, you could accidentally have match cos 3 and match cos 5 in the same match-all class definition, which would match nothing at all. That’s a good gotcha!
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BGP Route Reflectors (pages 404 – 409). I hadn’t appreciated the rules about what happens when you have some RR clients and some non-RR clients on the same hub, and more importantly, why. The answer is that all routes are reflected except non-RR-client to non-RR-client. For the why, you’ll have to read the book. Suddenly the concept of cluster-ids became crystal clear.
[Warning! Off Topic! Warning!]
Next week, he wants me to go into the Blues School with him, which would mean I would miss all that reading. Or am I just afraid of revealing how rusty my guitar technique really is?
Talking of guitars, isn’t Andy McKee incredible? I was lucky enough to see him in concert here in Luxembourg a few weeks ago, and he really can play this stuff:
Amazing! There are so many great guitarists around at the moment that I don’t know who gets my vote for the best guitarist in the world today: Andy McKee, Antoine Dufour, or Don Ross.
I also wanted to see if I could embed a YouTube clip in my blog. Seems I can.
