Learn Juniper and Cisco networking – with jokes!
In this first of a two-part post, I’m going to take you on a magical journey. And by “take you on a magical journey” I mean “teach you what the inet.3 table does on a Juniper router.” Which is basically the same thing as a magical journey, right?
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Network engineers often find they need a way to test something, and then take some action if that test fails. Well, you can do these tests oh-so-easily in Junos with a thing called Real-Time Performance Monitoring. RPM is what “other vendors” might call IP SLA. How do they work? Good question, Andrew! Let’s find out.
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Imagine a user who says they’re only able to access even-numbered IPs in a destination subnet. “Help!”, they say. “I can’t leave the office until this is fixed, and I need to leave now because my seven large sons require their tri-daily feed of protein shakes. They will whither and die unless I nourish them immediately. The fate of my powerful sons is in your hands, and yours alone.” This exact problem came in to us recently. Well, apart from the bit about the large sons.
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This is the third and final part of my whistle-stop tour of IS-IS, for people studying for their Juniper JNCIS-SP and JNCIS-ENT exams. In this post, we learn how to troubleshoot IS-IS. Are you wearing your safety hat? Then, let’s go!
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In Part 2 we take a deeper-dive into IS-IS. We do packet captures of LSAs, we look at the metrics, the Designated Intermediate-System, and we even explore our feelings together, so that we can finally find inner-peace with ourselves. Great!!!
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Here’s the first of our three-part beginners guide to IS-IS. We’ll compare it to OSPF; we’ll talk about Level 1 and Level 2; we’ll explain the bizarre addressing system; we’ll look at a basic config, and we’ll talk about why Googling for IS-IS is very different from Googling for ISIS.
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In the 90s, the big fashion was Tamagotchis. In 2017 it was fidget spinners. And of course, in 2018 there’s only one trend on everyone’s lips: route summarisation. In Junos there’s three ways to summarise routes. Want to know what they are? Well gosh damn, you’ve come to the right place!
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Want to learn how to configure Chassis Cluster, which lets you configure high-availability failover on Juniper firewalls? Good luck with the official documentation – it weighs in at precisely 638 pages long. 638 pages! That’s the length of two good books! Or one badly edited one. Anyway, this article is my attempt at boiling those 638 pages down into something a bit more manageable. You can thank me by emailing me £700,000.
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Once you’ve read my guide to the new link-state advertisement types in OSPFv3, give this post a read, where we take a deep-deep into the OSPFv3 database. Put your topology hat on: we’re going exploring.
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When I first heard that OSPFv3 introduced even more link-state advertisement (LSA) types, I despaired. As if the original seven didn’t take us long enough to memorise! Then I actually learned what they do – and honestly, it’s hard to imagine why we ever did it any differently. Let’s learn about them together!
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