Have you ever wondered what the Kubernetes fuss is all about? Why would you ever want to use it? Stuart Charlton tried to answer that question in the introduction part of his fantastic Kubernetes Networking Deep Dive webinar.

It’s almost exactly three months since I announced ipSpace.net going on an extended coffee break. We had some ideas of what we plan to do at that time, but there were still many gray areas, and thanks to tons of discussions I had with many of my friends, subscribers, and readers, they mostly crystallized into this:

You’re trusting me to deliver. We added a “you might want to read this first” warning to the checkout process, and there was no noticeable drop in revenue. Thanks a million for your vote of confidence!

TL&DR: Client clock skew could result in AWS authentication failure when running terraform apply

When I wanted to compare AWS and Azure orchestration speeds I encountered a crazy Terraform error message when running terraform apply:

module.network.aws_vpc.My_VPC: Creating...

Error: Error creating VPC: AuthFailure: 
AWS was not able to validate the provided access credentials
	status code: 401, request id: ...

Obviously I did all the usual stuff before googling for a solution:

Here’s a message I got from one of my subscribers (probably based on one of my recent public cloud rants):

TL&DR: The new release of netsim-tools includes unnumbered interfaces, configuration modules, and OSPF configuration.

In mid-March, we enjoyed another excellent presentation by Dinesh Dutt, this time focused on running OSPF in leaf-and-spine fabrics. He astonished me when he mentioned unnumbered Ethernet interfaces being available on all major network operating systems. It was time to test things out, and I wanted to use my networking simulation builder to build the test lab.

We’re in an unfortunate industry where you can’t learn everything there’s to know in 3 years and keep doing the same stuff for the next 30 years… but how do you keep learning? Andrew Owen documented what works for him in Learning without Burnout.

It’s amazing how easy it is to create a chatbot that will send messages to a Discord channel… just follow John Capobianco’s step by step tutorial.

In the second half of my chat with David Bombal we focused on automation and AI in networking. Even though we discussed many things, including the dangers of doing a repeatable job, and how to make yourself unique, David chose a nice click-bait headline Will AI Replace the Networking Engineers?. According to Betteridge’s law of headlines the answer is still NO, but it’s obvious AI will replace the low-level easy-to-automate jobs (as textile workers found out almost 200 years ago).

While pondering that statement, keep in mind that AI is more than just machine learning (the overhyped stuff). According to one loose definition, “Artificial intelligence (AI) refers to the simulation of human intelligence in machines that are programmed to think like humans and mimic their actions”

When I was complaining about the speed (or lack thereof) of Azure orchestration system, someone replied “I tried to do $somethingComplicated on AWS and it also took forever”

Following the “opinions are great, data is better” mantra (as opposed to “never let facts get in the way of a good story” supposedly practiced by some podcasters), I decided to do a short experiment: create a very similar environment with Azure and AWS.

I took simple Terraform deployment configuration for AWS and Azure. Both included a virtual network, two subnets, a route table, a packet filter, and a VM with public IP address. Here are the observed times:

TL&DR: Azure Route Server works as advertised. Setting it up is excruciatingly slow. You might want to start the process just before taking a long lunch break.

I decided to take Azure Route Server for a ride. Simple setup, two Networking Virtual Appliance (NVA) instances running Quagga to advertise a single prefix (just to see how multipathing works).

Here’s the diagram of what I set up:

TL&DR: You get unequal-cost multipath for free with distance-vector routing protocols. Implementing it in link state routing protocols is an order of magnitude more CPU-consuming.

Continuing our exploration of the Unequal-Cost Multipath world, why was it implemented in EIGRP decades ago, but not in OSPF or IS-IS?

Ignoring for the moment the “does it make sense” dilemma: finding downstream paths (paths strictly shorter than the current best path) is a side effect of running distance vector algorithms.

TL&DR: There cannot be a simple and easy recipe for success, or everyone else would be using it.

My recent chat with David Bombal about networking careers’ future resulted in tons of comments, including a few complaints effectively saying I was pontificating instead of giving out easy-to-follow recipes. Here’s one of the more polite ones:

No tangible solutions given, no path provided, no actionable advice detailed.

I totally understand the resentment. Like a lot of other people, I spent way too much time looking for recipes for success. It was tough to admit there are none for a simple reason: if there was a recipe for easy success, everyone would be using it, and then we’d have to redefine success. Nobody would admit that being average is a success, or as Jeroen van Bemmel said in his LinkedIn comment:

Success requires differentiation, which cannot be achieved by copying others. As Steve Jobs put it: “Be hungry, stay foolish”

I hope you’re aware that the venerable ping (and most of its variants) measures round-trip-time – how long it takes to get to the destination and back – but is there a way to measure one-way latency or find out asymmetric transit times?

Ben Cox found a way to use ICMP timestamps together with reasonably accurate NTP-derived time to do just that. More details in Splitting the ping (HT: Drew Conry-Murray).

A few weeks ago I enjoyed a long-overdue chat with David Bombal. David published the first part of it under the click-bait headline Is Networking Dead (he renamed it Is There any Future for Networking Engineers in the meantime).

According to Betteridge’s law of headlines the answer to his original headline is NO (and the second headline violates that law – there you go 🤷‍♂️). If you’re still interested in the details, watch the interview.

One of my subscribers sent me this question after watching the networking part of Introduction to Cloud Computing webinar:

Does anyone know what secret networking magic the Cloud providers are doing deep in their fabrics which are not exposed to consumers of their services?

TL&DR: Of course not… and I’m guessing it would be pretty expensive if I knew and told you.

However, one can always guess based on what can be observed (see also: AWS networking 101, Azure networking 101).