Troubleshooting a discrepancy between convergence time of different VRFs with identical settings, running over the same topology, I got the chance delve deeper into OSPF timers. Since it took a while to wrap my head around all the moving parts and I only fully grokked it after drawing everything on a whiteboard for a colleague, I decided to explain this thoroughly here.

This will be a bit of a long read. In short: If you don’t set your LSA accept timers lower than your LSA send timers, you will have to wait for your retransmission time-out get

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Day 10

The final day was just a short day, until noonish. Narbik explained some about redistribution and showed us some loops and how to fix them. It felt a bit rushed, but to be honest, I don’t how much more I could absorb. Afterwards, I tried to do some more troubleshooting labs, but I clearly want clear headed enough. So, I spent the final time chatting with my classmates.

Thanks everyone who was in this class with me. Especially Sylwia, David, Bernd, and Dan
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Day 8 and 9

The tiredness is taking it’s toll now. I really notice that I have more difficulties with the troubleshooting labs. I didn’t even have the energy to write a post yesterday evening. I am noticing that I am less focussed on all the troubleshooting labs. A few of us are going through them at a really rapid pace. I could keep up for a while, but at the last lab today I just had to give up. I couldn’t even troubleshoot the simplest issues, let alone the ramped up difficulties.
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Day 4 Troubleshooting tired typos

The processes do work. It really is a go slow to go fast. Build the foundations first, make sure everything is correct before moving on to anything dependant on the foundations. This makes problem domains small in your head and more easily solved. It is still easy to read over a typo (mpls ldp router-id loopback 1, instead of 0 for instance), but you will only be troubleshooting 2 or 3 devices at a time.
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