Amazon EKS Service Cluster

Amazon Elastic Kubernetes Service (Amazon EKS) is a fully managed Kubernetes service.

For creating a cluster on Kubernetes and launching WordPress and MYSQL on top of it tools required are as follows:

• aws cli
• kubectl
• eksctl

Creating a Kubernetes cluster :

First, an amazon IAM account is created with full Administration power. Download the credentials file and then use it to configure in CLI.

For launching a cluster we need to write a YML file with name cluster.yml as follows:

apiVersion: eksctl.io/v1alpha5
kind: ClusterConfig
metadata:
  name: eks-cluster
  region: ap-south-1
nodeGroups:
  - name: ng-1
    instanceType: t2.micro
    desiredCapacity: 2
    ssh:
      publicKeyName: mykey1122
  - name: ng-2
    instanceType: t2.small
    desiredCapacity: 1
    ssh:
      publicKeyName: mykey1122
  - name: ng-mixed
    minSize: 2
    maxSize: 5
    instancesDistribution:
      maxPrice: 0.017
      instanceTypes: ["t3.small", "t3.medium"] # At least one instance type should be specified
      onDemandBaseCapacity: 0
      onDemandPercentageAboveBaseCapacity: 50
      spotInstancePools: 2
    ssh:
      publicKeyName: mykey1122

Use the following command to create this cluster. The AWS UI shows the launched cluster.

eksctl create cluster -f cluster.yml 

cluster launching

cluster launched

Next update the kubeconfig file by command:

aws eks --region ap-south-1 update-kubeconfig --name eks-cluster

To attach EFS we need to create it from UI in the same VPC as of our node so that they can connect.

We create a new namespace for provisioner.

kubectl create ns provisionerns

We need to create efs-provisioner.yml and update the FILE_SYSTEM_ID , server & your provisioner _name in it.

kind: Deployment
apiVersion: apps/v1
metadata:
  name: efs-provisioner
spec:
  selector:
    matchLabels:
      app: efs-provisioner
  replicas: 1
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: efs-provisioner
    spec:
      containers:
        - name: efs-provisioner
          image: quay.io/external_storage/efs-provisioner:v0.1.0
          env:
            - name: FILE_SYSTEM_ID
              value: fs-a1058f70
            - name: AWS_REGION
              value: ap-south-1
            - name: PROVISIONER_NAME
              value: isha/aws-efs
          volumeMounts:
            - name: pv-volume
              mountPath: /persistentvolumes
      volumes:
        - name: pv-volume
          nfs:
            server: fs-a1058f70.efs.ap-south-1.amazonaws.com
            path: /

create using:

kubectl create - f create-efs-provisioner.yml -n provisionerns

For some extra security, we need to create the Cluster Role Binding File.

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: nfs-provisioner-role-binding
subjects:
  - kind: ServiceAccount
    name: default
    namespace: provisionerns
roleRef:
  kind: ClusterRole
  name: cluster-admin
  apiGroup: rbac.authorization.k8s.io

To run it use :

kubectl create - f create-rbac.yml -n provisionerns

Next, we create our own storage class.

kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: aws-efs
provisioner: isha/aws-efs
---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: efs-wordpress
  annotations:
    volume.beta.kubernetes.io/storage-class: "aws-efs"
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 10Gi
---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: efs-mysql
  annotations:
    volume.beta.kubernetes.io/storage-class: "aws-efs"
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 10Gi

For creating it use:

kubectl create - f create-storage.yml -n provisionerns

For deploying WordPress and MySQL database using EFS as storage we will use the following yml files:

deploy-mysql.yml

apiVersion: v1
kind: Service
metadata:
  name: wordpress-mysql
  labels:
    app: wordpress
spec:
  ports:
    - port: 3306
  selector:
    app: wordpress
    tier: mysql
  clusterIP: None
---
apiVersion: apps/v1 # for versions before 1.9.0 use apps/v1beta2
kind: Deployment
metadata:
  name: wordpress-mysql
  labels:
    app: wordpress
spec:
  selector:
    matchLabels:
      app: wordpress
      tier: mysql
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: wordpress
        tier: mysql
    spec:
      containers:
      - image: mysql:5.6
        name: mysql
        env:
        - name: MYSQL_ROOT_PASSWORD
          valueFrom:
            secretKeyRef:
              name: mysql-pass
              key: password
        ports:
        - containerPort: 3306
          name: mysql
        volumeMounts:
        - name: mysql-persistent-storage
          mountPath: /var/lib/mysql
      volumes:
      - name: mysql-persistent-storage
        persistentVolumeClaim:
          claimName: efs-mysql

deploy-wordpress.yml

apiVersion: v1
kind: Service
metadata:
  name: wordpress
  labels:
    app: wordpress
spec:
  ports:
    - port: 80
  selector:
    app: wordpress
    tier: frontend
  type: LoadBalancer
---
apiVersion: apps/v1 # for versions before 1.9.0 use apps/v1beta2
kind: Deployment
metadata:
  name: wordpress
  labels:
    app: wordpress
spec:
  selector:
    matchLabels:
      app: wordpress
      tier: frontend
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: wordpress
        tier: frontend
    spec:
      containers:
      - image: wordpress:4.8-apache
        name: wordpress
        env:
        - name: WORDPRESS_DB_HOST
          value: wordpress-mysql
        - name: WORDPRESS_DB_PASSWORD
          valueFrom:
            secretKeyRef:
              name: mysql-pass
              key: password
        ports:
        - containerPort: 80
          name: wordpress
        volumeMounts:
        - name: wordpress-persistent-storage
          mountPath: /var/www/html
      volumes:
      - name: wordpress-persistent-storage
        persistentVolumeClaim:
          claimName: efs-wordpress

kustomization.yml

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
secretGenerator:
- name: mysql-pass
  literals:
  - password= redhat
resources:
  - deploy-mysql.yaml
  - deploy-wordpress.yaml

By running the kustomization file the deploy-mysql.yml and deploy-wordpress.yml are also created. Use command:

kubectl create -k .

We get an IP of WordPress open it in the browser and set up your website and you are good to go.