Setting up Kubernetes

Kubernetes is made of many components that require careful configuration
Secure operation typically requires TLS certificates and a local CA

(certificate authority)
Setting up everything manually is possible, but rarely done

(except for learning purposes)
Let's do a quick overview of available options!

Local development

Are you writing code that will eventually run on Kubernetes?
Then it's a good idea to have a development cluster!
Development clusters only need one node
This simplifies their setup a lot:
- pod networking doesn't even need CNI plugins, overlay networks, etc.
- they can be fully contained (no pun intended) in an easy-to-ship VM image
- some of the security aspects may be simplified (different threat model)
Examples: Docker Desktop, k3d, KinD, MicroK8s, Minikube

(some of these also support clusters with multiple nodes)

Many cloud providers and hosting providers offer "managed Kubernetes"
The deployment and maintenance of the cluster is entirely managed by the provider

(ideally, clusters can be spun up automatically through an API, CLI, or web interface)
Given the complexity of Kubernetes, this approach is strongly recommended

(at least for your first production clusters)
After working for a while with Kubernetes, you will be better equipped to decide:
- whether to operate it yourself or use a managed offering
- which offering or which distribution works best for you and your needs

Pricing models differ from one provider to another
- nodes are generally charged at their usual price
- control plane may be free or incur a small nominal fee
Beyond pricing, there are huge differences in features between providers
The "major" providers are not always the best ones!

Most providers let you pick which Kubernetes version you want
- some providers offer up-to-date versions
- others lag significantly (sometimes by 2 or 3 minor versions)
Some providers offer multiple networking or storage options
Others will only support one, tied to their infrastructure

(changing that is in theory possible, but might be complex or unsupported)
Some providers let you configure or customize the control plane

(generally through Kubernetes "feature gates")

If you want to run Kubernetes yourselves, there are many options

(free, commercial, proprietary, open source ...)
Some of them are installers, while some are complete platforms
Some of them leverage other well-known deployment tools

(like Puppet, Terraform ...)
A good starting point to explore these options is this guide

(it defines categories like "managed", "turnkey" ...)

kubeadm is a tool part of Kubernetes to facilitate cluster setup
Many other installers and distributions use it (but not all of them)
It can also be used by itself
Excellent starting point to install Kubernetes on your own machines

(virtual, physical, it doesn't matter)
It even supports highly available control planes, or "multi-master"

(this is more complex, though, because it introduces the need for an API load balancer)

The resources below are mainly for educational purposes!
Kubernetes The Hard Way by Kelsey Hightower
- step by step guide to install Kubernetes on Google Cloud
- covers certificates, high availability ...
- “Kubernetes The Hard Way is optimized for learning, which means taking the long route to ensure you understand each task required to bootstrap a Kubernetes cluster.”
Deep Dive into Kubernetes Internals for Builders and Operators
- conference presentation showing step-by-step control plane setup
- emphasis on simplicity, not on security and availability

Doesn't set up Docker or any other container engine

(this is by design, to give us choice)
Doesn't set up the overlay network

(this is also by design, for the same reasons)
HA control plane requires some extra steps
Note that HA control plane also requires setting up a specific API load balancer

(which is beyond the scope of kubeadm)

???

:EN:- Various ways to install Kubernetes :FR:- Survol des techniques d'installation de Kubernetes