Kubernetes

Slides from the Kubernetes talk at OC Python - 6/5/2018

Transcript

1. Kubernetes OC Python June 5th 2018
2. Introduction - Nihara Thomas
3. Agenda • Kubernetes Intro • Why Kubernetes? • Kubernetes concepts • How you can start using Kubernetes • Demo • Resources • Q&A
5. What now? Kubernetes is an open-source system for automating deployment, scaling, and management of containerized applications. K8s == Kubernetes
6. But what’s the problem? • Multi-container, multi-host applications • High Availability • Scalability • Ease of Deployment
7. Solution... Container Orchestration frameworks Cluster Management Scheduling Containers Service Discovery Load Balancing Crash Recovery
8. And Kubernetes helps how? • Open source • Cloud Service Provider agnostic • Easy Upgrades and Rollbacks • Self-healing • Horizontal Scaling • Service Discovery and Load Balancing
9. Cool… so what do I need to know?
10. K8s Architecture
11. Kubernetes Objects • Persistent entities in the K8s system • Represent the state of your system • You create it, K8s makes sure it’s always there
12. K8s Objects - Namespace • Help divide cluster resources • Provide scope for names - isolation and security
13. K8s Objects - Deployment • Single instance of an application in the K8s system • Specifies containers that need to be run • Container Image and tag • Desired number of replicas
14. K8s Objects - Replica Set • Ensures that specified number of pods are running at any given time • Used by deployment to orchestrate pod creation, deletion and updates
15. K8s Objects - Pod • Basic building block of K8s • Encapsulates a container (or multiple containers) • Defines required storage resources • Specifications on how the container(s) should run
16. Deployment → ReplicaSet → Pod
17. K8s Objects - Service • Abstraction that defines a set of pods and policies by which they can be accessed
18. K8s Objects - Volume • Directory with (or without data) that is accessible to the container • Explicit lifetime - same as that of the Pod • Data persists across container restarts
19. K8s Objects - DaemonSet • Ensures that a Pod is run on all K8s nodes • Use case: ◦ Logs collection daemon such as FluentD
20. K8s Objects - Job • K8s Cron • Job creates a pod(s) and ensures that it runs to completion ◦ No image ◦ Can run a command directly ◦ Restarts pod in case of failure ◦ # of successful completions desired can be specified
21. Interacting with K8s Objects • K8s API directly • Kubectl → CLI utility that calls the K8s api for you
22. Try Kubernetes • Minikube - local K8s cluster ◦ minikube start • Deploy K8s cluster on a CSP ◦ K8s the Hard Way - Kelsey Hightower • Self-hosted K8s
23. Let’s see K8s at work .... Link to Demo app
24. Resources • Try Kubernetes • Kubernetes Comic • Official K8s documentation
25. Questions?