Old Dog Kubernetes Presentation

Who Am I?

• Tom Purl (https://www.tompurl.com)

  

Who Am I?

• Automation Engineer at Wi-Tronix LLC
  • My views are my own and do not represent my employer
• Likes to build cool things and share them with others

Why do you need this?

• You want a high-level introduction to Kubernetes

• Want to understand the benefits of "thinking like a Kubernetes admin"

What Do I Promise?

• No hype, buzzwords or BS

Thinking Like a Kubernetes Admin

• Not only does your toolset change, but your inputs and outputs also change.

How Will We Learn?

• Part 1: Cool, open-ended demo!
• Part 2: Analyze What We Did

Part 0 - Background

What's Kubernetes?

• A platform for managing VM's and containers
• Free and Open Source

What's a Microservice

• Anything you can trick your boss into thinking it is 😉
• Small chunk of code that does one thing well

What's Smaller Than a Microservice?

• Functions!
• e.g. AWS Lambda, OpenFaaS

Part 1 - Deploying an API and Function Gateway On a New Kubernetes Cluster

What Are We Deploying?

OpenFaaS

OpenFaaS

• Function and API gateway (like Amazon Lambda)
• Free and open source

A Couple of Functions

We'll be deploying some of the functions from this lab:

• https://github.com/openfaas/workshop

Demo

Creating our Kubernetes Cluster

Deploy OpenFaaS

• https://github.com/openfaas/workshop/blob/master/lab1b.md
• https://github.com/openfaas/faas-netes/blob/master/chart/openfaas/README.md

Deploying Functions

• https://github.com/openfaas/workshop/blob/master/lab2.md

Playtime!

Part 2 - Deeper Dive

What Did We Just Do?

Declared Our System, Not Installed It

• No Puppet, no shell scripts
• Use YAML¹ to declare what your system should look like

Primitives

• Great, extendable layer of abstraction

Primitive Examples

• Pods
• Deployment
• App
• Service
• Ingress
• PersistentVolume

You Can Add Your Own

• The Kubernetes project maintainers can't think of everything :-)
• Examples
  • CertificateRequest

What Didn't We Just Do?

We Didn't Have To Worry About…

Networking

• Automatic DNS Configuration
  

  kubectl get services -n openfaas -o wide
  

Farming / Clustering

• Which node runs what?

Low-Level Docker Commands

• Just specify the image and tag

Monitoring

• Liveness / Readiness / Startup Probes
• Automatica Failover

Auto-Scaling

• You can configure your system to spin up more pods based on conditions
• It's called a Horizontal Pod Autoscaler

Gripe Time

What Could Be Better?

Persistent Storage is Weird and Difficult

• Very vendor-centric
• You get the impression that you have to use S3 or distributed storage but you can still use NFS :^D
• Not fleshed out as well as the other Kubernetes primitives

Load Balancing is Vendor-Specific

• Every vendor handles load-balancing in a unique way

Ingress Configuration Is Very Vendor Specific

• You have to change your config based on your brand of ingress

Resources

Books

Kubernetes Up and Running

• A little dated but free and a good start on the basics

Running Kubernetes…

On Your Laptop!

• kind

On Your Rasperry Pi!

• K3S - Lightweight Kubernetes
• Will it Cluster?

On Your x64 Home Lab!

• Rancher
• K3S - Lightweight Kubernetes

In the Cloud!

The ones I've tried in my order of preference:

• Digital Ocean
• Linode
• Google
• Lots of others (AWS, Azure, etc.)

Questions?

Thank you!