Steps to create Replica sets in the Kubernetes

In this blog, we will show you the Steps to create Replica sets in the Kubernetes environment.

REQUIREMENTS

• 2 Node Cluster ( 1 Master VM with 2 Nodes)

• Kubernetes Components

INFRASTRUCTURE OVERVIEW

• We have already installed and configured the 2 Node cluster in our demo environment.

• Please check the URL https://www.assistanz.com/steps-to-install-kubernetes-cluster-manually-using-centos-7/ for more information.

PODS OVERVIEW

• Currently, there are four orphan PODS which was created using the replication controller.

• All the POD’s are labeled with app=web env=test.

• We will show you how to add the orphan pods into a Replica Set.

REPLICA SET BENEFITS

CREATING A NEW REPLICA SET

• From the master node, open the default text editor.

• Add the below script in the YML file.

apiVersion: apps/v1beta2
kind: ReplicaSet
metadata:
    name: rs-web
spec:
    replicas: 4
    selector:
       matchLabels:
          app: web
    template:
       metadata:
          labels:
             app: web
             env: test
       spec:
          containers:
          - name: rs-pod
            image: nginx

• Save and close the file.

• Use the below command to create a new replica set.

kubectl apply -f rs.yml

• A new replica set is created successfully.

VERIFYING THE REPLICA SET

• Use the below command to view the list of replica set available in your environment.

kubectl get rs

• It added the orphan pods into the replica set. Also, it has not created any additional pods for the replica set.

• We can also describe the replica set using the below command.

Syntax: kubectl describe rs <replica set name>

Example: kubectl describe rs rs-web

• There are more expressions available for the replica set and will share that information in future blogs.

REFERENCE

https://kubernetes.io/docs/concepts/workloads/controllers/replicaset/

Thanks for reading this blog. We hope it was useful for you to learn to about the steps to create Replica sets in the Kubernetes