K3S: Introduction to Kubernetes

Introduction to Kubernetes#

Ah, Kubernetes—the orchestration behemoth that devs both love and fear. It’s like a Swiss Army knife for containerized applications, except instead of just cutting things, it also schedules, scales, and occasionally makes you question your career choices.

So, what is Kubernetes and why do we willingly subject ourselves to its complexities? Simply put, Kubernetes (or K8s, because apparently, we’re all too lazy to type the full name) is a container orchestration platform. It automates the deployment, scaling, and management of containerized applications. In other words, it prevents your containers from running wild like an unsupervised toddler.

Key components of Kubernetes architecture#

Before you can master Kubernetes, you need to understand its moving parts. Here’s the breakdown:

Control Plane#

• API Server: The boss. Every command and request go through this gatekeeper.
• Controller Manager: Ensures the desired state of the system. It’s like a strict parent making sure everything stays in order.
• Scheduler: Decides which worker node gets to host your container. Basically, the Kubernetes equivalent of a hotel receptionist.
• etcd: Stores all cluster data. Lose this, and you’ve basically lost your cluster. No pressure.

Worker Nodes#

• Kubelet: The agent running on every worker node, taking orders from the API Server like a well-trained intern.
• Kube Proxy: Handles networking. Makes sure your services can talk to each other instead of giving each other the silent treatment.
• Container Runtime: The thing that actually runs your containers. Docker, containerd, whatever—this is what makes your applications work.

Benefits of container orchestration#

• Automated scaling (because nobody likes manually resizing deployments at 2 AM)
• Self-healing (crashed pods get restarted automatically, like a Phoenix rising from the ashes—except less mythical and more practical)
• Efficient resource utilization (less wasted CPU, less angry DevOps teams)

Understanding K3s#

Now, Kubernetes is great and all, but let’s be real—it’s a resource-hungry beast. Enter K3s, the diet version of Kubernetes. It’s lightweight, fast, and perfect for edge computing, IoT, and developers who just want a cluster running without crying.

What is K3s?#

K3s is a slimmed-down Kubernetes distribution, designed for low-resource environments. It keeps all the good stuff while ditching the unnecessary bloat.

Why use K3s over standard Kubernetes?#

• It’s tiny: A single binary under 100MB. Kubernetes, on the other hand, feels like it’s made of boulders.
• Easy install: One command, and it’s up. No need to spend hours reading Stack Overflow posts.
• Low resource footprint: Runs on a Raspberry Pi, because why not?

K3s features and advantages#

• Lightweight and optimized for edge computing
• Single binary, reduced dependencies
• Simplified installation and reduced resource footprint
• Built-in SQLite support (because etcd is overrated)

Kubernetes vs. K3s: Key Differences#

Installing K3s#

Alright, enough talk. Let’s get this thing installed.

System requirements for K3s#

• At least 512MB RAM (but really, do yourself a favor and go for 1GB+)
• A Linux-based system (or a workaround for Windows/macOS)
• A stable internet connection (because downloading things is kinda required)

Installing K3s on Linux#

The beauty of K3s? Installation is ridiculously simple:

curl -sfL https://get.k3s.io | sh -
systemctl status k3s  # Verify installation

Boom. That’s it.

Installing K3s on Windows (using WSL2)#

• Install WSL2 and Ubuntu
• Run the same Linux install command inside WSL2

Installing K3s on macOS (using Multipass or Rancher Desktop)#

• Install Multipass or Rancher Desktop
• Deploy a Linux VM and follow the Linux installation steps

Verifying K3s installation#

Make sure your cluster is alive:

kubectl get nodes

If it shows Ready, congratulations! If not, check your logs and prepare for troubleshooting.

Hands-On Exercise#

Let’s get practical! Do this to make sure you didn’t just install K3s for nothing.

Install K3s on a local VM or cloud instance#

Pick your poison—AWS, GCP, DigitalOcean, or your own laptop.

Verify the cluster is running correctly#

Run:

kubectl get nodes

If you see a node with Ready status, you’re good. If not, time to start debugging!

Deploy a simple pod using kubectl run#

Let’s deploy an Nginx container because that’s what everyone does when testing Kubernetes:

kubectl run myapp --image=nginx --port=80

Then check if it’s running:

kubectl get pods

If it’s there, congratulations! You just deployed your first containerized app on K3s.

That’s it! You now have a lightweight Kubernetes cluster running in no time. Go forth and orchestrate responsibly. And remember—Kubernetes is a tool, not a lifestyle. Don’t let it consume you. 😆