My New SR-MPLS Course, and Krzysztof’s SRv6 Blogs
My new four-day instructor-led SR-MPLS course is now live! In addition, my colleague Krzysztof Szarkowicz has written many free blog posts on SRv6. Click this post to find out all about it.
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isis
IS-IS and Unnumbered Ethernet Interfaces in Junos
There’s a trick you can use to massively reduce the number of IPv4 addresses you need in your network. With a little tweaking and a little bit of love, you don’t need to use addresses at all on point-to-point Ethernet links. Let me show you how.
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Junos: IS-IS Study Notes, Part 5 – Troubleshooting (For JNCIS-SP and JNCIS-ENT Students)
It’s the fifth and final part of our lessons on IS-IS! You’re now ready to learn how to troubleshoot and verify everything you’ve done so far. You’re really close to the finish line, so don’t give up!
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MPLS Segment Routing, Part 2: Junos Config!
It’s time to learn how to configure MPLS segment routing in Junos! In this second part of my ongoing series I show you how easy it is to use SR as a replacement for LDP. The config is easy, and you’ll be itching to do it by the time you read this post.
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MPLS Segment Routing, Part 1: The Theory (Beginner’s Guide)
Every year, more folks are talking abouts segment routing for MPLS. Want to know what the fuss is about? Start here! This post gives you the high-points of some of the most important parts of the theory. Node SIDs, Adjacency SIDs, traffic-engineered LSPs, shortest path LSPs, and more are covered here. Read it and level up!
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Junos: IS-IS Study Notes, Part 4 – Levels, Areas, The Attached Bit, and Default Routes
The fourth part in this intro to IS-IS series tackles areas, and how they’re different to levels. A lot of new students confuse them, and a lot of documentation gets it wrong too! This post clears everything up for you, and will make you super confident. You’ll also learn about IS-IS default routes, and route leaking from L2 to L1. Give it a click!
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CLEAN UP YOUR ROUTING TABLE! REMOVING POINT-TO-POINT SUBNETS FROM IS-IS, IN JUNOS
Some ISPs like to remove point-to-point prefixes from IS-IS. This keeps their routing tables small and easier to read. But how does it work? Doesn’t this break things? What are the trade-offs? This post shows you how to configure this solution, and the things you’ll want to consider if you deploy it. It’s super-cool, and you’ll definitely enjoy seeing the mechanics in action!
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MAXIMISE YOUR JUNOS NETWORK WITH MPLS, PART 1: RSVP BANDWIDTH & PRIORITIES
RSVP lets us create LSPs that reserve bandwidth in advance. And that’s exactly what this three-part blog post series is all about! In this first post we’re going to learn how we combine bandwidth and priorities to get the most out of the bandwidth in our network. Click here for good times!
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REDISTRIBUTING YOUR ENTIRE IS-IS NETWORK BY MISTAKE: BEWARE THIS DEFAULT BEHAVIOUR!
If you leave IS-IS to its default config, you could cause something big to impact your network! And chances are, even if you think you know what that impact is, you might not have worked out the whole story. Click here to read the lesson I learned in my lab!
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INTERPROVIDER OPTION A, ON JUNIPER JUNOS ROUTERS (INCLUDES FULL TOPOLOGY CONFIG!) (JNCIP-SP, JNCIE-SP)
Ever wondered whether it’s possible to stretch an MPLS VPN across two ISPs? Well, indeed it is! In fact, there’s three ways to do it, and in this post we learn all about the method officially known as “Option A”.
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