Posts on CloudCat Digital

Retiring WordPress: a byte-identical migration to Hugo and GitHub Pages

Mon, 06 Jul 2026 00:00:00 +0000

How we moved a WordPress site off AWS onto Hugo and GitHub Pages without visitors noticing — capture, verify byte-for-byte, cut over DNS, and stop paying for an ALB.

System Administrator Appreciation Day

Fri, 25 Jul 2025 00:00:00 +0000

On the last Friday of July (this year, July 25, 2025), we celebrate System Administrator Appreciation Day to honour these silent guardians of our digital world.

Sending good vibes and a massive high‑five to all the sudo scientists pulling on‑call rotations and hanging out in those late‑night Slack channels, keeping the world online. You’re the heartbeat of every business out there 😻

ref: https://sysadminday.com/

Cluster Autoscaler VS Karpenter

Sun, 26 Jan 2025 00:00:00 +0000

Proposal: Migration from Cluster Autoscaler to Karpenter for EKS Cluster

Overview

The most common approach to scaling Kubernetes clusters in AWS is to use Cluster Autoscaler (CA), which automatically adjusts the number of nodes based on pod resource requirements. However, CA has limitations when managing mixed-instance Auto Scaling Groups (ASG), leading to inefficiencies in scaling down nodes. To address these issues, we propose migrating to Karpenter, a Kubernetes-based node provisioning solution that offers advanced features like direct EC2 provisioning and customizability. This document outlines the technical steps, pros and cons, and migration plan for transitioning from Cluster Autoscaler (CA) to Karpenter in an EKS environment. The change aims to address inefficiencies in scaling down mixed-instance Auto Scaling Groups (ASG) and improve provisioning flexibility by leveraging Karpenter’s advanced capabilities.

Building a wordpress-as-a-service platform on AWS with Terraform

Wed, 08 Jan 2025 00:00:00 +0000

A practical guide to hosting a PHP blog on AWS using Terraform. Automate infrastructure, manage certificates, secure and scale.

Hashicorp Vault Client Optimization

Thu, 26 Dec 2024 00:00:00 +0000

Optimizing Vault Costs with `serviceaccount_name` for Identity Aliases

Hashicorp Vault SaaS bills on client usage, and a client is everything from a user to a machine. More on this here. The problem is that when a developer removes a chart and redeploys it, vault will count the Kubernetes ServiceAccount as a distinct new app, which isn’t quite true, because it’s the same app we had before and we were billed for.

A Beginner's Guide to DNS

Sun, 26 May 2024 00:00:00 +0000

A Beginner’s Guide to DNS - From Domain Purchase to Establishing Your Online Presence

The Common Query: What Happens After Buying a Domain?

As an IT professional with a sysadmin background and cloud infrastructure focus, I often get DNS-related questions from programmers and colleagues who are just starting out with their own websites. One common confusion that arises post-purchase is about the role and setup of DNS hosting. This post aims to clarify these concepts, using my own experience with setting up https://cloudcat.digital as a practical example.

Integrating Helm Hooks with HashiCorp Vault for Cloud Migrations

Sun, 12 May 2024 00:00:00 +0000

Managing Secrets in Kubernetes with Helm and HashiCorp Vault

In the dynamic landscape of cloud migrations, securely and efficiently managing application configurations, particularly secrets, is a critical task. This article explores a practical scenario where an organization is migrating its applications from on-premises infrastructure to Amazon EKS, using HashiCorp Vault’s CSI driver to handle secrets. Here, we’ll dive into the challenges and solutions of using environment variables to access these secrets—a common yet sensitive practice—and provide a step-by-step guide to implementing robust solutions using Helm hooks.

Embracing Open Container Initiative for Helm Charts

Sun, 28 Apr 2024 00:00:00 +0000

A New Perspective on Helm Charts

Whale hello there (docker pun) DevOps enthusiasts! As someone who’s been navigating the waters of AWS and Helm for years, I’ve largely relied on the tried-and-tested methods like ChartMuseum and S3 backends for managing Helm charts. Occasionally, I’ve also pulled charts directly from version control when the stakes weren’t too high on audit trails, because it’s straightforward and gets the job done when conditions allow.

Microservices VS Serverless

Sun, 14 Apr 2024 00:00:00 +0000

In the dynamic world of software architecture, the debate between microservices and serverless functions (like AWS Lambda) is similar to the classic face-off between Ryu and Ken in the Street Fighter world. Both have their strengths, their unique moves, and their situational advantages. As developers, we’re often in the position to make a choice between the two, so let’s break down the details in a clear, concise, and human manner.

Making Caching Work for You in CI

Thu, 14 Mar 2024 00:00:00 +0000

A Practical Guide for GitHub Self-Hosted Runners

Hey everyone, today let’s talk about something that can make a real difference in your CI pipelines: effective caching. If you’ve been following along, you know we’ve explored using Docker registry mirror before. In our last post, we talked about the context and challenge of CI cache in a dynamic and fully scalable environment. Since our setup is like a revolving door with nodes coming and going based on demand, holding onto a Docker cache is like trying to catch smoke with your bare hands. So, when it comes to GitHub Actions self-hosted on EKS, especially with scale sets, caching needs a bit more attention.

GitHub Actions, self-hosted runners with Scale-Sets tips and tricks

Thu, 29 Feb 2024 00:00:00 +0000

As someone who’s spent a fair bit of time tinkering with CI/CD pipelines and automating infrastructure, I’ve really started to see the value in GitHub Actions, particularly after moving away from Jenkins. My journey took an exciting turn when I began experimenting with self-hosted GitHub Actions runners on Kubernetes, using the summerwinds actions runner controller. Things got even more interesting when I shifted to scale-sets, thanks to GitHub embracing the ARC project.

DevOps and DevOps Accessories

Sat, 10 Feb 2024 00:00:00 +0000

Remember Hank Hill from “King of the Hill”? He was all about propane and propane accessories. That’s kind of like me but with DevOps instead. And like Hank’s, my passion with computers started in my childhood, in the ’90s, a time when they were not just scarce but symbolized a window to a whole new world for me. The first time I encountered a Commodore-like PC sparked a whole new level of excitement and my fascination only grew as I discovered the magic of graphics and network capabilities.