Ethan Banks On productivity.

NMC DOiT Vol.2 Scenario 1 Day 5


Okay, my brain is blown right now. I’m tired, and I can’t think. I was trying hard to complete scenario 1 tonight, but it’s not going to happen. I’m stuck on the multicast section, trying to make sense out of what’s going on. The multicast stumper is to work around an RPF problem that has come up because of the frame-relay network. So for the multicast part of this scenario to work correctly, the IP routing table has to be just-so, converged in my lab the same as it’s converged in NMC’s lab. It’s not. I noticed that a lot of my routes have equal-cost paths, meaning that I have a redistribution problem.  NMC’s lab has essentially no equal-cost routes. Specifically, I have a problem where redistribution from 2 different points is looking like equal-cost routes to this particular router that’s integral to making the multicast scenario work. And I’m too wiped to debug the redistribution right now. I’m pretty sure the issue is that I’m redistributing routes I shouldn’t be from the parallel redistribution routers, but figuring out all the route-maps I’d need to put in to fix it just isn’t on tonight’s menu.

Besides multicast, I still have Catalyst & Catalyst 3560 Specialties and QoS sections still to go. So, time-wise, I’m way over 8 hours, in no small part because of trying to work through all the lab bugs I’ve had with cabling and IOS images. The lab has been spaced out over too many days, and it’s getting hard to keep straight what interfaces go where, etc. I’m tempted just to chalk the whole thing up as a learning experience, save & blow away all the configs, and go on to Scenario 2. Then later on, come back to Scenario 1 and debug the mess I’ve made, and/or start it over again. But I’m not going to do anything right now, because I’m cranky and irritated. I don’t like to make decisions when I’m upset. While I feel like moving on to Scenario 2, I know that I haven’t taken away everything I could be learning from Scenario 1. Therefore, I feel like I should be walking back through Scenario 1 with a fine-tooth comb to see what I screwed up, not just wussing out and moving on.

NMC talks about “The Golden Moment” – when you’ve got all your routing and IGP distribution done, connectivity from anywhere to anywhere. If you’re on the CCIE lab pace, you should be at the Golden Moment around the 4 hour mark, leaving the subsequent 4 hours for all of the application and service stuff. So, I think the big take-away lesson for me today is to make sure that I’ve REALLY reached the Golden Moment when I think I have. In this scenario, I really haven’t yet, and I’m paying for it in the multicast scenario, big-time.

I’ll make up my mind tomorrow whether I’m going to keep plodding on another night or 2 with Scenario 1, or whether I move on to Scenario 2.

1 comment

  • Sometimes it is just best to walk away for the night and come back to it the next day. You will usually find the problem after clearing your head.

By Ethan Banks
Ethan Banks On productivity.

You probably know Ethan Banks because he writes & podcasts about IT. For example, he co-authored "Computer Networks Problems & Solutions" with Russ White.

This site is Ethan on productivity--not tech so much.

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