RCs

Ensures that an instance of an image is being run with the specific number of copies.

Replica sets - new (beta) improved version of RCs

nodejs-controller.yaml

apiVersion: v1
kind: ReplicationController
metadata:
    name: node-js
    labels:
        name: node-js
spec:
    replicas: 3
    selector:
        name: node-js
    template:
        metadata:
            labels:
                name: node-js
        spec:
            containers:
            - name: node-js
              image: jonbaier/node-express-info:latest
              ports:
              - containerPort: 80