Kubernetes is a platform of application patterns. These patterns make workloads easier to run, to administer, and to keep running. Each pattern is represented by one controller in Kubernetes. This is an introduction to built-in controllers in Kubernetes for different kinds of workloads. https://kubernetes.io/

1. Running Workloads in Kubernetes
Janet Kuo, Software Engineer, Google

2. https://goo.gl/dWYJq4

3. https://goo.gl/2NLT0f
VP of Software Architecture @Spire.

4. Concept
| Kubernetes: a platform for application patterns
| Pod: a single instance of an application in Kubernetes
| Controller: manages replicated pods for an application pattern

5. Master node Worker node
Worker node

6. Master node Worker node
Worker node
Pod
Container Container
Pod
Container Container

7. Master node Worker node
Worker node
Pod
Container Container
Pod
Container Container
C

8. 4 Common, General Patterns
| Stateless
| Stateful
| Daemon
| Batch

9. 4 Common, General Patterns
| Stateless: web frontends, web servers
| Stateful
| Daemon
| Batch

10. 4 Common, General Patterns
| Stateless: web frontends, web servers
| Stateful: databases, message queues
| Daemon
| Batch

11. 4 Common, General Patterns
| Stateless: web frontends, web servers
| Stateful: databases, message queues
| Daemon: logs collection, node monitoring
| Batch

12. 4 Common, General Patterns
| Stateless: web frontends, web servers
| Stateful: databases, message queues
| Daemon: logs collection, node monitoring
| Batch: processing of independent work items

13. Stateless: Deployment
| Availability
| Scale, Deploy, Rolling Update
| e.g. Web apps, mobile backends, API servers, ...

14. kubectl
Master node Worker node
Worker node
Pod
Container Container
Pod
Container Container
Service
C
async
Demo: github.com/janetkuo/k8s-demos/tree/master/dep

15. Stateful: StatefulSet
| Consistency
| Stable identity and state
| Ordered deployment, scaling, deletion
| e.g. Databases, caches, message queues, ...

16. kubectl
Master node Worker node
Worker node
Pod 0
Container Container
Pod 1
Container Container
Service
C
async
Demo: github.com/janetkuo/k8s-demos/tree/master/stateful

17. Daemon: DaemonSet
| One per node
| Node labels
| e.g. Logs collection daemon, node monitoring daemon, ...

18. kubectl
Master node Worker node
Worker node
Pod
Container Container
Pod
Container Container
Service
C
async
Demo: github.com/janetkuo/k8s-demos/tree/master/ds

19. Batch: Jobs
| Parallel + Complete
| Related but independent work
| e.g. Emails to send, frames to render, ...

20. kubectl
Master node Worker node
Worker node
Pod
Container Container
Pod
Container Container
C
async
Demo: github.com/janetkuo/k8s-demos/tree/master/jobs

21. Recap
| Stateless: Deployment; availability
| Stateful: StatefulSet; consistency
| Daemon: DaemonSet; one per node
| Batch: Job; parallel to completion

22. Where do I start?
| Helm: The Kubernetes Package Manager
github.com/kubernetes/helm
| Helm Charts: Curated applications for Kubernetes
github.com/kubernetes/charts

23. How do I customize?
| Kubernetes is extensible!
| Write your own controllers
| e.g. github.com/upmc-enterprises/elasticsearch-operator
github.com/coreos/etcd-operator

24. Kubernetes is Open
github.com/kubernetes/kubernetes
kubernetes.io
slack.k8s.io / @janet
@kubernetesio / @janet_kuo