Microservices Deployment on EKS

Step-00: What are Microservices?

• Understand what are microservices on a very high level

Step-01: What are we going to learn in this section?

• We are going to deploy two microservices.
  • User Management Service
  • Notification Service

Usecase Description

• User Management Create User API will call Notification service Send Notification API to send an email to user when we create a user.

List of Docker Images used in this section

Application Name	Docker Image Name
User Management Microservice	stacksimplify/kube-usermanagement-microservice:1.0.0
Notifications Microservice V1	stacksimplify/kube-notifications-microservice:1.0.0
Notifications Microservice V2	stacksimplify/kube-notifications-microservice:2.0.0

Step-02: Pre-requisite -1: AWS RDS Database, ALB Ingress Controller & External DNS

AWS RDS Database

• We have created AWS RDS Database as part of section 06-EKS-Storage-with-RDS-Database
• We even created a externalName service: 01-MySQL-externalName-Service.yml in our Kubernetes manifests to point to that RDS Database.

ALB Ingress Controller & External DNS

• We are going to deploy a application which will also have a ALB Ingress Service and also will register its DNS name in Route53 using External DNS
• Which means we should have both related pods running in our EKS cluster.
• We have installed ALB Ingress Controller as part of section 08-01-ALB-Ingress-Install
• We have installed External DNS as part of section 08-06-01-Deploy-ExternalDNS-on-EKS

# Verify alb-ingress-controller pod running in namespace kube-system
kubectl get pods -n kube-system

# Verify external-dns pod running in default namespace
kubectl get pods

Step-03: Pre-requisite-2: Create Simple Email Service - SES SMTP Credentials

SMTP Credentials

• Go to Services -> Simple Email Service
• SMTP Settings --> Create My SMTP Credentials
• IAM User Name: append the default generated name with microservice or something so we have a reference of this IAM user created for our ECS Microservice deployment
• Download the credentials and update the same for below environment variables which you are going to provide in kubernetes manifest 04-NotificationMicroservice-Deployment.yml

AWS_MAIL_SERVER_HOST=email-smtp.us-east-1.amazonaws.com
AWS_MAIL_SERVER_USERNAME=****
AWS_MAIL_SERVER_PASSWORD=***
AWS_MAIL_SERVER_FROM_ADDRESS= [email protected] 

• Important Note: Environment variable AWS_MAIL_SERVER_FROM_ADDRESS value should be a valid email address and also verified in SES.

Verfiy Email Addresses to which notifications we need to send.

• We need two email addresses for testing Notification Service.
• Email Addresses
  • Verify a New Email Address
  • Email Address Verification Request will be sent to that address, click on link to verify your email.
  • From Address: [email protected] (replace with your ids during verification)
  • To Address: [email protected] (replace with your ids during verification)
• Important Note: We need to ensure all the emails (FromAddress email) and (ToAddress emails) to be verified here.
  • Reference Link: https://docs.aws.amazon.com/ses/latest/DeveloperGuide/verify-email-addresses.html
• Environment Variables
  • AWS_MAIL_SERVER_HOST=email-smtp.us-east-1.amazonaws.com
  • AWS_MAIL_SERVER_USERNAME=*****
  • AWS_MAIL_SERVER_PASSWORD=*****
  • AWS_MAIL_SERVER_FROM_ADDRESS=[email protected]

Step-04: Create Notification Microservice Deployment Manifest

• Update environment Variables for Notification Microservice
• Notification Microservice Deployment

          - name: AWS_MAIL_SERVER_HOST
            value: "smtp-service"
          - name: AWS_MAIL_SERVER_USERNAME
            value: "AKIABCDEDFASUBKLDOAX"
          - name: AWS_MAIL_SERVER_PASSWORD
            value: "Bdsdsadsd32qcsads65B4oLo7kMgmKZqhJtEipuE5unLx"
          - name: AWS_MAIL_SERVER_FROM_ADDRESS
            value: "[email protected]"

Step-05: Create Notification Microservice SMTP ExternalName Service

apiVersion: v1
kind: Service
metadata:
  name: smtp-service
spec:
  type: ExternalName
  externalName: email-smtp.us-east-1.amazonaws.com

Step-06: Create Notification Microservice NodePort Service

apiVersion: v1
kind: Service
metadata:
  name: notification-clusterip-service
  labels:
    app: notification-restapp
spec:
  type: ClusterIP
  selector:
    app: notification-restapp
  ports:
  - port: 8096
    targetPort: 8096

Step-07: Update User Management Microservice Deployment Manifest with Notification Service Environment Variables.

• User Management Service new environment varibales related to Notification Microservice in addition to already which were configured related to MySQL
• Update in 02-UserManagementMicroservice-Deployment.yml

          - name: NOTIFICATION_SERVICE_HOST
            value: "notification-clusterip-service"
          - name: NOTIFICATION_SERVICE_PORT
            value: "8096"    

Step-08: Update ALB Ingress Service Kubernetes Manifest

• Update Ingress Service to ensure only target it is going to have is User Management Service
• Remove /app1, /app2 contexts

    # External DNS - For creating a Record Set in Route53
    external-dns.alpha.kubernetes.io/hostname: services.kubeoncloud.com, ums.kubeoncloud.com
spec:
  rules:
    - http:
        paths:
          - path: /* # SSL Redirect Setting
            backend:
              serviceName: ssl-redirect
              servicePort: use-annotation                   
          - path: /*
            backend:
              serviceName: usermgmt-restapp-nodeport-service
              servicePort: 8095              

Step-09: Deploy Microservices manifests

# Deploy Microservices manifests
kubectl apply -f V1-Microservices/

Step-10: Verify the Deployment using kubectl

# List Pods
kubectl get pods

# User Management Microservice Logs
kubectl logs -f $(kubectl get po | egrep -o 'usermgmt-microservice-[A-Za-z0-9-]+')

# Notification Microservice Logs
kubectl logs -f $(kubectl get po | egrep -o 'notification-microservice-[A-Za-z0-9-]+')

# External DNS Logs
kubectl logs -f $(kubectl get po | egrep -o 'external-dns-[A-Za-z0-9-]+')

# List Ingress
kubectl get ingress

Step-11: Verify Microservices health-status via browser

# User Management Service Health-Status
https://services.kubeoncloud.com/usermgmt/health-status

# Notification Microservice Health-Status via User Management
https://services.kubeoncloud.com/usermgmt/notification-health-status
https://services.kubeoncloud.com/usermgmt/notification-service-info

Step-12: Import postman project to Postman client on our desktop.

• Import postman project
• Add environment url
  • https://services.kubeoncloud.com (Replace with your ALB DNS registered url on your environment)

Step-13: Test both Microservices using Postman

User Management Service

• Create User
  • Verify the email id to confirm account creation email received.
• List User
  • Verify if newly created user got listed.

Step-14: Rollout New Deployment - Set Image Option

# Rollout New Deployment using Set Image
kubectl set image deployment/notification-microservice notification-service=stacksimplify/kube-notifications-microservice:2.0.0 --record=true

# Verify Rollout Status
kubectl rollout status deployment/notification-microservice

# Verify ReplicaSets
kubectl get rs

# Verify Rollout History
kubectl rollout history deployment/notification-microservice

# Access Application (Should see V2)
https://services.kubeoncloud.com/usermgmt/notification-health-status

# Roll back to Previous Version
kubectl rollout undo deployment/notification-microservice

# Access Application (Should see V1)
https://services.kubeoncloud.com/usermgmt/notification-health-status

Step-15: Rollout New Deployment - kubectl Edit

# Rollout New Deployment using kubectl edit, change image version to 2.0.0
kubectl edit deployment/notification-microservice

# Verify Rollout Status
kubectl rollout status deployment/notification-microservice

# Verify ReplicaSets
kubectl get rs

# Verify Rollout History
kubectl rollout history deployment/notification-microservice

# Access Application (Should see V2)
https://services.kubeoncloud.com/usermgmt/notification-health-status

# Roll back to Previous Version
kubectl rollout undo deployment/notification-microservice

# Access Application (Should see V1)
https://services.kubeoncloud.com/usermgmt/notification-health-status

Step-16: Rollout New Deployment - Update manifest & kubectl apply

# Rollout New Deployment by updating yaml manifest 2.0.0
kubectl apply -f kube-manifests/

# Verify Rollout Status
kubectl rollout status deployment/notification-microservice

# Verify ReplicaSets
kubectl get rs

# Verify Rollout History
kubectl rollout history deployment/notification-microservice

# Access Application (Should see V2)
https://services.kubeoncloud.com/usermgmt/notification-health-status

# Roll back to Previous Version
kubectl rollout undo deployment/notification-microservice

# Access Application (Should see V1)
https://services.kubeoncloud.com/usermgmt/notification-health-status

Step-17: Clean-up

kubectl delete -f kube-manifests/