USING WILDCARD MASKS TO FILTER ODD OR EVEN NUMBERED IP ADDRESSES: JUNIPER JUNOS & CISCO IOS

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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Junos: IS-IS Study Notes, Part 3 – Interfaces, Metrics, the DIS, and Pseudonodes

It’s the third part in our series on IS-IS! In this post you’re going to learn about interface types, broadcast interfaces, metrics, and the OSPF equivalent of the designated router – the “designated intermediate system”, or DIS. It’s way more efficient than how OSPF does it. I think you’re gonna enjoy this one!

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Junos: IS-IS Study Notes, Part 1 – For Juniper’s JNCIS-SP and JNCIS-ENT Exams

Here’s the first post in my five-part guide to IS-IS. Wow, what a Christmas treat! In this first post we compare IS-IS to OSPF; we’ll talk about Level 1 and Level 2; we’ll explain the unique 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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JUNOS: CHASSIS CLUSTERS – A BEGINNERS GUIDE TO JUNIPER SRX HIGH AVAILABILITY

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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