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Technology Short Take 152

Welcome to Technology Short Take #152! Normally I’d publish a Technology Short Take in the morning on a Friday, but I really wanted to get this one out so I’m making it live late in the day on a Monday. Here’s hoping I’ve included some content below that you find useful!


  • I was (and am) familiar with RFC 1918 and the concept of non-routable address spaces. However, I was not familiar with the term “bogons” to refer to such prefixes that should not be publicly routed. Thanks to this article, that oversight is now corrected. Oh, and the article shares a handy Python script to help implement bogon filtering in NSX-T.
  • Koyeb describes, at a high level, the global networking stack for their serverless platform. Components involved include the open source Kuma service mesh (in turn leveraging Envoy), anycast BGP, and mutual TLS (mTLS).
  • Ivan Pepelnjak does a great job of describing all the things you really shouldn’t do (or don’t really need to do) when trying to deal with migrating container hosts in a data center fabric. In truth, the answer is exactly as Ivan says at the top of the article: when it comes to migrating container hosts, you don’t. (Seriously.)



Cloud Computing/Cloud Management

  • Anders Eknert shows how to do—or at least provides a framework on getting started with—dynamic policy composition with Open Policy Agent (OPA) in this blog post from April 2021.
  • Here’s an article on how to get started with OrgFormation.
  • This workshop on using Graviton2 on AWS is pretty neat.
  • Xavier Avrillier writes about how to workaround a vSphere CSI controller CrashLoopBackoff when using Cluster API for vSphere (CAPV).
  • Jorge de la Cruz shares how to install Kubernetes on Ubuntu 20.04. Most of my readers are probably already familiar with this process, but I wanted to share it here just in case.
  • Marc Brooker has a pair of articles on circuit breakers and retries that are, in my opinion, worth reading (part 1 on circuit breakers is here, part 2 on retries is here). And when I say “circuit breakers,” I’m not talking about your electrical panel, either. Read the articles if you’re unfamiliar with the concept of circuit breakers in modern distributed systems.
  • For folks who may be just getting started with Terraform, here’s a tutorial on how to deploy EC2 instances in AWS using Terraform.
  • I just came across this relatively-new EKS News site. Have a look at the archives for links to all the issues of EKS News. It’s a shame the site doesn’t appear to have an RSS/Atom feed…

Operating Systems/Applications




  • Normally Ivan Pepelnjak’s articles land in the “Networking” section, but this time Ivan is squarely discussing virtualization when he talks about running an Ubuntu VM on an M1-based Mac. I guess this is just yet another example of how fluid the “boundaries” between technical disciplines has become.

Career/Soft Skills

  • I really enjoyed this post on lessons learned by moving the office home. There’s several nuggets in here that I need to apply to my next office move (which will be happening in about a month or so, if I don’t run into any more delays).
  • I like this idea of thinking about an intention instead of resolutions.

That’s a wrap! I’ll be back in a couple of weeks with another Technology Short Take; until then, keep exploring, keep learning, and keep sharing! If you want to contact me—perhaps to provide some feedback, suggest a site you’ve found helpful, or just to say hello—feel free to contact me on Twitter or hit me up in any one of a number of Slack communities. I’d love to hear from you.

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