Category: worth reading

The results of netlab integration tests are stored in YAML files, making it easy to track changes improvements with Git. However, once I added the time of test and netlab version to the test results, I could no longer use git diff to figure out which test results changed after a test run – everything changed.

For example, these are partial test results from the OSPFv2 tests:

Vini Motta decided to use AI on ipSpace.net content to find what it would recommend as the projects to work on in order to become employable in 2025. Here are the results he sent me; my comments are inline on a gray background.

Network Automation with Python

Project: Automate basic network tasks like device configuration, backup, or monitoring using Python scripts.

Dalton Ortega, Cisco Modeling Labs Product Manager, sent me the following email as a response to my Configuring IP Addresses Won't Make You an Expert blog post:

First, your statement on Autonetkit is indeed correct. We had removed that from the product due to lack of popularity. That being said, in our roadmap we are looking at methods to reintroduce on-the-fly configuration as well as enhancing our sample labs library to make getting started with CML easier.

Secondly, CML can be run in full IaC mode because of the API-first build. In fact, many of our customers are using CML as an automated test/validation bed for their CI/CD pipelines. Tools like Ansible and Terraform are available to facilitate this inside CML too. For more details, read:

• Get Started With Terraform and Cisco Modeling Labs
• How to Use Ansible with CML

Another year is almost gone, and it’s time for my traditional “I will disappear until mid-January” retreat (also, don’t expect me to read my email until I’m back).

I hope you’ll also be able to disconnect from the crazy pace of the networking world, forget the “AI will make networking engineers obsolete” shenanigans (hint: SDN did not), and focus on your loved ones. I would also like to wish you all the best in 2025!

I will probably get bored sometime in late December, so expect a few new netlab features in early January.

Addy Osmani published an excellent overview of the challenges of AI-assisted coding. They apply equally well to the “AI will generate device configurations for me” or “AI will troubleshoot my network” ideas (ignoring for the moment the impact of the orders-of-magnitude smaller training set), so it’s definitely worth reading.

I particularly liked the “‌AI is like having a very eager junior developer on your team” take, as well as the description of the “70% problem” (AI will get you 70% there, but the last 30% will be frustrating) – a phenomenon perfectly illustrated by the following diagram by Forrest Brazeal:

When I discovered GitHub Codespaces (thanks to a pointer by Roman Dodin), I did the absolute minimum of research to get netlab up and running in a container to enable Codespaces-based labs (BGP, IS-IS) and netlab examples.

However, if you want to know the behind-the-scenes details, you MUST read the Codespaces for Network Engineers and Educators deep dive by Julio Perez.

One of the key arguments against stretched clusters (and similar stupidities) I used in my Disaster Recovery Myths presentation was the SSD read latency versus cross-site round-trip time.

Thanks to Networking Notes, I found a great infographic I can use in my next presentation (bonus points: it also works great in a terminal when fetched with curl) and a site that checks the latency of your web site from various vantage points.

Would you like to start a tech blog but don’t know how to do it? Ethan Banks put together a phenomenal how-to guide in his Developing Content & Gathering Research For Your Tech Blog article.

Oh, and please use Hugo (or similar) and use walled gardens like LinkedIn solely to post summaries and links to your content. You want to be in control and retain ownership of your work, right?

Dmytro Shypovalov wrote a great series of detailed posts on Egress Peer Engineering:

• Poor Man’s Traffic Engineering
• Egress Peer Engineering: Basics
• Egress Peer Engineering: Building Blocks

Have fun!

Retirement obviously does not sit well with my friend Tiziano Tofoni; the English version of his IPv6 book just came out.

It is a bit sad, though, that we still need “how to use IPv6” books when the protocol is old enough to enjoy a nice glass of whiskey (in the US) trying to drown its sorrow at its slow adoption.

Nick Buraglio and Brian E. Carpenter published a free, open-source IPv6 textbook.

The book seems to be in an early (ever-evolving) stage, but it’s well worth exploring if you’re new to the IPv6 world, and you might consider contributing if you’re a seasoned old-timer.

It would also be nice to have a few online labs to go with it ;)

Urs Baumann loves hands-on teaching and created tons of lab exercises to support his Infrastructure-as-Code automation course.

During the summer, he published some of them in a collection of GitHub repositories and made them work in GitHub Codespaces. An amazing idea well worth exploring!

Vincent Bernat documented a quirk I hope you’ll never see outside of a CCIE lab: combining BGP confederations with AS-override can generate endless AS paths.

I agree entirely with his conclusions (avoid both features). However, I still think that replacing an AS within the confederation part of an AS path (which should belong to a single well-managed AS) is not exactly the most brilliant idea I’ve seen.

I never mastered the fine art of polite diplomatic sarcasm. Brad Casemore is a virtuoso – you’ll love his take on Google’s Quarterly Results: Investors Begin Questioning Efficacy of GenAI Investments.

Dmytro Shypovalov wrote a fantastic article explaining the basics of MPLS-based Segment Routing. It’s pretty much equivalent to everything I ever wrote about SR-MPLS but in a much nicer package. Definitely a must-read.