Microservices Deployment on EKS¶

Step-00: What are Microservices?¶

Understand what are microservices on a very high level

Kubernetes Manifests¶

01020304050607

#01-MySQL-externalName-Service.yml
apiVersion: v1
kind: Service
metadata:
  name: mysql
spec:
  type: ExternalName
  externalName: usermgmtdb.cxojydmxwly6.us-east-1.rds.amazonaws.com

#02-UserManagementMicroservice-Deployment.yml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: usermgmt-microservice
  labels:
    app: usermgmt-restapp
spec:
  replicas: 1
  selector:
    matchLabels:
      app: usermgmt-restapp
  template:
    metadata:
      labels:
        app: usermgmt-restapp
    spec:
      initContainers:
        - name: init-db
          image: busybox:1.31
          command: ['sh', '-c', 'echo -e "Checking for the availability of MySQL Server deployment"; while ! nc -z mysql 3306; do sleep 1; printf "-"; done; echo -e "  >> MySQL DB Server has started";']
      containers:
        - name: usermgmt-restapp
          image: stacksimplify/kube-usermanagement-microservice:1.0.0
          ports:
            - containerPort: 8095
          env:
            - name: DB_HOSTNAME
              value: "mysql"
            - name: DB_PORT
              value: "3306"
            - name: DB_NAME
              value: "usermgmt"
            - name: DB_USERNAME
              value: "dbadmin"
            - name: DB_PASSWORD
              valueFrom:
                secretKeyRef:
                  name: mysql-db-password
                  key: db-password
            - name: NOTIFICATION_SERVICE_HOST
              value: "notification-clusterip-service"
            - name: NOTIFICATION_SERVICE_PORT
              value: "8096"                            
          livenessProbe:
            exec:
              command:
                - /bin/sh
                - -c
                - nc -z localhost 8095
            initialDelaySeconds: 60
            periodSeconds: 10
          readinessProbe:
            httpGet:
              path: /usermgmt/health-status
              port: 8095
            initialDelaySeconds: 60
            periodSeconds: 10          
---
# Kubernetes Secrets
apiVersion: v1
kind: Secret
metadata:
  name: mysql-db-password
#type: Opaque means that from kubernetes's point of view the contents of this Secret is unstructured, it can contain arbitrary key-value pairs. In contrast, there is the Secret storing ServiceAccount credentials, or the ones used as ImagePullSecret . These have a constrained contents.
type: Opaque
data:
  # Output of echo -n 'dbpassword11' | base64
  db-password: ZGJwYXNzd29yZDEx

#03-UserManagement-NodePort-Service.yml
apiVersion: v1
kind: Service
metadata:
  name: usermgmt-restapp-nodeport-service
  labels:
    app: usermgmt-restapp
  annotations:
  #Important Note:  Need to add health check path annotations in service level if we are planning to use multiple targets in a load balancer  
    alb.ingress.kubernetes.io/healthcheck-path: /usermgmt/health-status
spec:
  type: NodePort
  selector:
    app: usermgmt-restapp
  ports:
  - port: 8095
    targetPort: 8095

#04-NotificationMicroservice-Deployment.yml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: notification-microservice
  labels:
    app: notification-restapp
spec:
  replicas: 1
  selector:
    matchLabels:
      app: notification-restapp
  template:
    metadata:
      labels:
        app: notification-restapp
    spec:
      containers:
        - name: notification-service
          image: stacksimplify/kube-notifications-microservice:1.0.0
          ports:
            - containerPort: 8096
          imagePullPolicy: Always
          env:
            - name: AWS_MAIL_SERVER_HOST
              value: "smtp-service"
            - name: AWS_MAIL_SERVER_USERNAME
              value: "AKIASUF7HC7SQJ6BCLVS"
            - name: AWS_MAIL_SERVER_PASSWORD
              value: "BARcmLiC68wgmhTy/cQvz/E8vFzeizGqdeASNtCs6+Nv"
            - name: AWS_MAIL_SERVER_FROM_ADDRESS
              value: "stacksimplify@gmail.com"

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

#06-NotificationMicroservice-ClusterIP-Service.yml
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

#07-ALB-Ingress-SSL-Redirect-ExternalDNS.yml
# Annotations Reference:  https://kubernetes-sigs.github.io/aws-alb-ingress-controller/guide/ingress/annotation/
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: eks-microservices-demo
  labels:
    app: usermgmt-restapp
  annotations:
    # Ingress Core Settings  
    kubernetes.io/ingress.class: "alb"
    alb.ingress.kubernetes.io/scheme: internet-facing
    # Health Check Settings
    alb.ingress.kubernetes.io/healthcheck-protocol: HTTP 
    alb.ingress.kubernetes.io/healthcheck-port: traffic-port
    alb.ingress.kubernetes.io/healthcheck-interval-seconds: '15'
    alb.ingress.kubernetes.io/healthcheck-timeout-seconds: '5'
    alb.ingress.kubernetes.io/success-codes: '200'
    alb.ingress.kubernetes.io/healthy-threshold-count: '2'
    alb.ingress.kubernetes.io/unhealthy-threshold-count: '2'
    ## SSL Settings
    alb.ingress.kubernetes.io/listen-ports: '[{"HTTPS":443}, {"HTTP":80}]'
    alb.ingress.kubernetes.io/certificate-arn: arn:aws:acm:us-east-1:180789647333:certificate/9f042b5d-86fd-4fad-96d0-c81c5abc71e1
    #alb.ingress.kubernetes.io/ssl-policy: ELBSecurityPolicy-TLS-1-1-2017-01 #Optional (Picks default if not used)    
    # SSL Redirect Setting
    alb.ingress.kubernetes.io/actions.ssl-redirect: '{"Type": "redirect", "RedirectConfig": { "Protocol": "HTTPS", "Port": "443", "StatusCode": "HTTP_301"}}'   
    # 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                                   
# Important Note-1: In path based routing order is very important, if we are going to use  "/*", try to use it at the end of all rules.

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= use-a-valid-email@gmail.com

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: stacksimplify@gmail.com (replace with your ids during verification)
- To Address: dkalyanreddy@gmail.com (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=stacksimplify@gmail.com

AWS EKS - Elastic Kubernetes Service - Masterclass¶

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: "stacksimplify@gmail.com"

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/