## Demystifying Kubernetes

## Issues of traditional application management - Unexpected application crash <!-- .element: class="fragment" data-fragment-index="1" --> - Resource saturation: usually CPU, Memory and diskspace<!-- .element: class="fragment" data-fragment-index="2" --> - Traffic surge ! <!-- .element: class="fragment" data-fragment-index="3" --> - Hardware/Cloud provider failures <!-- .element: class="fragment" data-fragment-index="5" -->

### Fixing these in traditional manner - Waking up in the middle of the night ! <!-- .element: class="fragment" data-fragment-index="1" --> - Ping the server to see if it's up ? <!-- .element: class="fragment" data-fragment-index="2" --> - Check the logs or analyze the issue ? <!-- .element: class="fragment" data-fragment-index="3" --> - Restart App or Provision more h/w (-+)<!-- .element: class="fragment" data-fragment-index="4" --> - Check if application metrics are satisfactionary. <!-- .element: class="fragment" data-fragment-index="5" --> - Apart from calling 1800-DEPLOYMENT !

### Aftermath - Humans add latency which causes increased MTTR. <!-- .element: class="fragment" data-fragment-index="1" --> - Possibility of making mistakes ! <!-- .element: class="fragment" data-fragment-index="2" --> - Business taking a hit ! 🔥 <!-- .element: class="fragment" data-fragment-index="3" --> - Developer Happiness goes down the hill ! 🤯 <!-- .element: class="fragment" data-fragment-index="4" --> - Dev effort grows propotional to no./size of application <!-- .element: class="fragment" data-fragment-index="5" -->

### Building the perfect system - Remove "humans" from equation 🤖 <!-- .element: class="fragment" data-fragment-index="1" --> - System should be proactive NOT reactive. <!-- .element: class="fragment" data-fragment-index="2" --> - System has to understand the rules of application. <!-- .element: class="fragment" data-fragment-index="3" --> - Ability to scale hardware and software. <!-- .element: class="fragment" data-fragment-index="4" --> - All of this should be done without waking up developer ! <!-- .element: class="fragment" data-fragment-index="5" -->


## Enter Kubernetes  - Image sourced from fineartamerica.com

### Pre-requisites for Kubernetes - Kubernetes doesn't know how to run an application, It only knows to spin up container images. <!-- .element: class="fragment" data-fragment-index="1" --> - Can containarize applications with Docker and pass it to Kubernetes. <!-- .element: class="fragment" data-fragment-index="2" --> - Kubernetes Configuration YAML DSL <!-- .element: class="fragment" data-fragment-index="3" -->

### Container - Container are a isolated runtime which runs on host, created by running images. - We use Dockerfiles to create images. 

### Pods - Kubernetes abstraction of containers to provide additional configurations to containers. 

### Hands On setup ! - brew install docker - brew install kubernetes-cli - brew cask install minikube - brew cask install virtualbox [Give permission to add virtualization driver] - minikube start - github.com/albertpaulp/demystifying-kubernetes-demo

### How Kubernetes works ! - K8 knows how to deploy containers. <!-- .element: class="fragment" data-fragment-index="1" --> - K8 knows how to check health of application. <!-- .element: class="fragment" data-fragment-index="2" --> - K8 can restart/reschedule application if case if it's unhealthy. <!-- .element: class="fragment" data-fragment-index="3" --> - K8 can scale up/down underlying hardware and software. <!-- .element: class="fragment" data-fragment-index="4" --> - K8 can be configured for a High Availability architecture. <!-- .element: class="fragment" data-fragment-index="5" -->

### Kubernetes Architecture - One master node to rule 'em all. (Can have multiple master for HA) 

### Kubernetes Deployment Components - Deployment configuration - Service configuration

### Demo Time ! - Use minikube if that's setup. - If not, use katacoda.com/courses/kubernetes/playground - Create deployment <!-- .element: class="fragment" data-fragment-index="1" --> - Show Fault tolerence <!-- .element: class="fragment" data-fragment-index="2" --> - Show scaling <!-- .element: class="fragment" data-fragment-index="3" -->

### Thank You for your time 🍪 ### Questions, keep 'em coming.. Shoutouts to Mohit and Parthesh 🍻 ^{@albertpaulp</sup </textarea> </section> </div> </div>}