Devops

Modernising .NET projects for .NET Core and beyond!

The world of .NET is going through a transformation. The .NET Framework is reaching end of life, .NET Core is an increasingly feature rich and robust platform to develop solutions which target Linux, MacOS, embedded devices, containers and more. There's also the .NET Standard. But what does this mean for .NET Framework projects? In this article I'll describe how to modernise your .NET Framework projects for .NET Core, the .NET Standard and .
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Observations, tips and tricks for the CKA certification

In this article I'll share some observations, tips and tricks for the Linux Foundation's “Certified Kubernetes Administrator certification and exam. I've been operating Kubernetes in multiple environments for a few years now. I thought this would be an easy certification to get, but I was surprised by how hard it was! I took this exam without doing any formal training, I mostly focused on the areas of the curriculum which I knew I was a little weak at.
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Supercharge your Java Projects with Conventional Commits, Semantic Versioning and Semantic Releases

In this article we'll look at a few simple techniques which can really supercharge your Java project and make them much easier to work with! Semantic Versioning Why Does This Matter? The Semantic Versioning Specification Using Semantic Versions The Challenge of Semantic Versions Conventional Commits Time for Magic Enforcing Conventional Commits with Git Hooks How the Hook Works Creating the Initial Release Go Forth And DevOps The Gradle Version That's It tl;dr If you know the concepts, then just jump straight to my fork of standard-version at github.
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Effective Shell for Beginners

I have rebuilt my “Effective Shell” series as an online book - it's available now on: https://effective-shell.com The whole site is built from a GitHub repo at github.com/dwmkerr/effective-shell. It is open for contributions, changes, issues and suggestions. I've also added a comment section to each page to get input. To keep the material as accessible as possible, I have added a new section for beginners, to help anyone who has not used a shell before.
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Effective Shell Part 7: The Subtleties of Shell Commands

In this chapter, we'll take a look at the various different types of shell commands that exist and how this can affect your work. By the end of this chapter, you might even be able to make sense of the horrifying and perfectly syntactically valid code below: which $(where $(what $(whence $(whereis who)))) Part 1: Navigating the Command Line Part 2: Become a Clipboard Gymnast Part 3: Getting Help Part 4: Moving Around Part 5: Interlude - Understanding the Shell Part 6: Everything You Don't Need to Know About Job Control Part 7: The Subtleties of Shell Commands What Are Commands?
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Effective Shell Part 6: Everything You Don't Need To Know About Job Control

Job control is a feature of most shells, which is generally not particularly intuitive to work with. However, knowing the basics can help prevent you from getting yourself into a tangle, and can from time to time make certain tasks a little easier. In this chapter, we'll look at the main features of job control, why it can be a problematic, and some alternatives. Part 1: Navigating the Command Line Part 2: Become a Clipboard Gymnast Part 3: Getting Help Part 4: Moving Around Part 5: Interlude - Understanding the Shell Part 6: Everything You Don't Need to Know About Job Control Part 7: The Subtleties of Shell Commands What Is Job Control?
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Effective Shell Interlude: Understanding the Shell

This is the first ‘interlude’ in my Effective Shell series. These interludes give some background, history or more flavour to some of the topics. Part 1: Navigating the Command Line Part 2: Become a Clipboard Gymnast Part 3: Getting Help Part 4: Moving Around Part 5: Interlude - Understanding the Shell Part 6: Everything You Don't Need to Know About Job Control Part 7: The Subtleties of Shell Commands This one should be high-level enough for even non-technical readers to enjoy (or at least understand!
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Manipulating Istio and other Custom Kubernetes Resources in Golang

In this article I'll demonstrate how to use Golang to manipulate Kubernetes Custom Resources, with Istio as an example. No knowledge of Istio is needed, I'll just use it to demonstrate the concepts! Istio is a highly popular Service Mesh platform which allows engineers to quickly add telemetry, advanced traffic management and more to their service-based applications. One interesting element of how Istio works is that when deployed into a Kubernetes cluster, many key configuration objects are handled as Custom Resources.
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Patching Kubernetes Resources in Golang

Recently I needed to be able to quickly adjust the number of replicas in a Kubernetes Replication Controller. The original solution I'd seen pulled down the spec, modified it, then updated it. There's a better way! There's a patch API for Kubernetes resources. Patching resources is faster and easier than pulling them and updating the spec wholesale. However, the documentation is a little limited. After some trial and error I got it working, here's the solution.
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mongo-monitor - a simple CLI to monitor your MongoDB cluster

The mongo-monitor CLI is a lean and simple tool to check the status of a MongoDB server or cluster. The code is on GitHub: github.com/dwmkerr/mongo-monitor Here's how it looks in action: In this animation I am monitoring a simple sharded cluster, and running some example maintenance operations, adding a node to a replicaset, stepping down a primary and shutting down a replicaset node. A simple CLI which shows the status in real-time can be very useful to keep open when performing admin, letting you see how your changes affect the cluster as you work on it.
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