Kubernetes – ReplicaSet Explained

• You have a pod running some applications and users are accessing it.
• If the pod goes down for any reason, then the app is down and needs manual intervention to bring it back online.
• A ReplicaSet’s purpose is to maintain a stable set of replica Pods running at any given time.
• As such, it is often used to guarantee the availability of a specified number of identical Pods.
• Below is a sample ReplicaSet Definition file for your reference.

apiVersion: apps/v1
kind: ReplicaSet
metadata: 
  name: myapp-repl
  labels:
    app: myapp
    type: front-end
spec: 
  template:
    metadata:
      name: myapp-pod
      labels:
        name: myapp
        type: front-end
    spec:
      containers:
      - name: nginx-controller
        image: nginx
  replicas: 3
  selector:
    matchlabels:
      type: front-end