DEV Community: Matthew Evan Eichler

swiss tables in go

Matthew Evan Eichler — Wed, 26 Feb 2025 10:04:55 +0000

AWS CDK Typescript: Adding Extra Nodes to Study Kubernetes Availability

Matthew Evan Eichler — Wed, 05 Feb 2025 11:06:56 +0000

This installment of the AWS CDK Typescript code for setting up an environment for studying Kubernetes Fundamentals (course LFS258 from the Linux/Cloud Native Foundation) shows how to easily add three extra EC2 instances for playing with higher availability options for your learning Kubenetes cluster.

I used extra1 for the HA Proxy then extra2 and extra3 to join Control Plane Nodes with the cluster. You can, of course, play with these extra instances as you will:

$ kubectl get nodes
NAME     STATUS   ROLES           AGE     VERSION
cp       Ready    control-plane   21d     v1.31.1
extra2   Ready    control-plane   4d20h   v1.30.9
extra3   Ready    control-plane   4d20h   v1.30.9
k8swk1   Ready    control-plane   21d     v1.31.1

Pull Request #4

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Matthew Evan Eichler — Tue, 04 Feb 2025 19:38:28 +0000

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AWS CDK Typescript: Adding Custom Initialisation to EC2 Instances

Matthew Evan Eichler — Wed, 22 Jan 2025 11:06:39 +0000

In my last post, I introduced an AWS CDK Typescript example repository which can build and destroy two EC2 instances if you are taking the Linux Foundation LFS258 Kubernetes Fundamentals self-paced course. You can work on the course and tear down the Stacks at the end of the day to avoid any extra Cloud Costs.

But doing this over and over again can be tedious setting up the Ubuntu packages everytime you start the next day over. This is where the User Data for AWS EC2 virtuals machines comes in. You can introduce a script that gets executed each time a new EC2 instance is created, sparing you some extra time.

aventinesolutions/lfx-study-aws-cdk-kubernetes Pull Request #3

In this case,

We first want to prepare our Ubuntu boxes with some changes to system configuration and ensure a couple of modules are loaded.
We also use apt to fully update all packages
Then we set up the package signing keys in a GnuPG keyring.
Next, we install the Docker, Kubernetes and Helm packages required before we can start building our cluster according to the course.

After the Cloud Formation Stack has completed, how do I know my initialisation script worked correctly? I found the output in /var/log/cloud-init-output.log ...

...
Preparing to unpack .../helm_3.16.3-1_amd64.deb ...
Unpacking helm (3.16.3-1) ...
Setting up helm (3.16.3-1) ...
Processing triggers for man-db (2.10.2-1) ...
... etc

You can use this as a pattern when you need also need a few set-up customisations for the EC2 image you use. However, if you have many changes from your chosen base image, then it would probably scale-up better to create your own custom Amazon Machine Image [AMI] from an EC2 instance that you have thoroughly tested (refer to this post "Build Your Own Ubuntu AMI" from @matrey Mathieu Rey)

Run Commands When You Launch an EC2 Instance with User Data Input on AWS Docs

AWS CDK Typescript Simple Project for Cloud Formation of Resources Required for Kubernetes Study

Matthew Evan Eichler — Mon, 30 Dec 2024 12:27:34 +0000

This repository demonstrates using the AWS Cloud Development Kit (CDK) to build infrastructure for self-paced Kubernetes courses and Linux Foundation certifications. It showcases cross-stack dependencies, where the VPC and security groups are defined in a separate stack from the compute resources. This approach avoids the potential for unintended destruction often associated with nested stacks, especially in complex CloudFormation deployments. The Kubernetes node scaling is easily configurable to accommodate advanced courses (e.g., three worker and three control plane nodes). Developed using JetBrains IntelliJ Ultimate. Feedback welcome!

aventinesolutions/lfx-study-aws-cdk-kubernetes

Rust is Still Promising as a Replacement for C++

Matthew Evan Eichler — Fri, 20 Dec 2024 16:30:33 +0000

Jet Brains Developers' Survey for 2024 ... Rust is still promising as a memory safe replacement for C++ with the highest popularily, along with Go Lang, among Developers who "plan to adopt a new language." Both languages have robust concurrency in mind.

Multiple Stacks in AWS CDK (Typescript)

Matthew Evan Eichler — Wed, 11 Dec 2024 14:49:50 +0000

It is possible to build multiple, separate Cloud Formation Stacks in a single AWS CDK project. Perhaps that is better when scaling up ... I mean, does this avoid accidental destruction when using Nested Stacks? How to Create Multiple Stacks