GKE with Kubernetes Gateway API - Load Balancer Traffic Splitting

Step-01: Introduction¶

Create GCP Application Load Balancer using Kubernetes Gateway API, Static IP for Load Balancer, Self-signed SSL with Google Cloud Certificate Manager, Traffic Splitting
Approach-1: Using Kubernetes YAML Manifests
Approach-2: Using Terraform Manifests

Step-02: Approach-1: Using Kubernetes YAML Manifests¶

Step-02-01: NO CHANGES from previous demo¶

c4-01-gateway.yaml
c4-02-gateway-http-to-https-route.yaml

Step-02-02: Create Regional Static IP¶

# Create Regional Load Balancer IP
gcloud compute addresses create my-regional-ip1 \
    --region="REGION_NAME" \
    --project=my-project-id

gcloud compute addresses create my-regional-ip1 \
    --region="us-central1" \
    --project=gcplearn9 \
    --network-tier="STANDARD"

# List IP Addresss    
gcloud compute addresses list

Step-02-03: Create Self-signed SSL certificates¶

# Change Directory
cd p2-regional-k8sresources-yaml/self-signed-ssl

# Create your app1 key:
openssl genrsa -out app1.key 2048

# Create your app1 certificate signing request:
openssl req -new -key app1.key -out app1.csr -subj "/CN=app1.stacksimplify.com"

# Create your app1 certificate:
openssl x509 -req -days 7300 -in app1.csr -signkey app1.key -out app1.crt

Step-02-04: Create Certificate Manager Regional cert and cert map and cert map entry¶

# Create SSL Cert using Certificate Manager
gcloud certificate-manager certificates create "CERTIFICATE_NAME" \
    --certificate-file="CERTIFICATE_FILE" \
    --private-key-file="PRIVATE_KEY_FILE" \
    --location="REGION"
Important Note: If no location provided it is global certificate

# Change Directory
cd p2-regional-k8sresources-yaml/self-signed-ssl

# Create Regional Cert: us-central1
gcloud certificate-manager certificates create "app1-us-central1-cert" \
    --certificate-file="app1.crt" \
    --private-key-file="app1.key" \
    --location="us-central1"    

# Regional: List Certificates
gcloud certificate-manager certificates list --location us-central1

Step-02-05: c1-01-myapp1-v1-deployment.yaml¶

apiVersion: apps/v1
kind: Deployment 
metadata: #Dictionary
  name: myapp1-deployment-v1
spec: # Dictionary
  replicas: 2
  selector:
    matchLabels:
      app: myapp1-v1
  template:  
    metadata: # Dictionary
      name: myapp1-pod-v1
      labels: # Dictionary
        app: myapp1-v1  # Key value pairs
    spec:
      containers: # List
        - name: myapp1-container-v1
          image: ghcr.io/stacksimplify/kubenginx:1.0.0
          ports: 
            - containerPort: 80  
          resources:
            requests:
              memory: "256Mi" # 128 MebiByte is equal to 135 Megabyte (MB)
              cpu: "250m" # `m` means milliCPU
            limits:
              memory: "512Mi"
              cpu: "400m"  # 1000m is equal to 1 VCPU core

Step-02-06: c1-02-myapp1-v1-clusterip-service.yaml¶

apiVersion: v1
kind: Service 
metadata:
  name: myapp1-service-v1
spec:
  type: ClusterIP # ClusterIP, # NodePort # LoadBalancer
  selector:
    app: myapp1-v1
  ports: 
    - name: http
      port: 80 # Service Port
      targetPort: 80 # Container Port

Step-02-07: c2-01-myapp1-v2-deployment.yaml¶

apiVersion: apps/v1
kind: Deployment 
metadata: #Dictionary
  name: myapp1-deployment-v2
spec: # Dictionary
  replicas: 2
  selector:
    matchLabels:
      app: myapp1-v2
  template:  
    metadata: # Dictionary
      name: myapp1-pod-v2
      labels: # Dictionary
        app: myapp1-v2  # Key value pairs
    spec:
      containers: # List
        - name: myapp1-container-v2
          image: ghcr.io/stacksimplify/kubenginx:2.0.0
          ports: 
            - containerPort: 80  
          resources:
            requests:
              memory: "256Mi" # 128 MebiByte is equal to 135 Megabyte (MB)
              cpu: "250m" # `m` means milliCPU
            limits:
              memory: "512Mi"
              cpu: "400m"  # 1000m is equal to 1 VCPU core

Step-02-08: c2-02-myapp1-v2-clusterip-service.yaml¶

apiVersion: v1
kind: Service 
metadata:
  name: myapp1-service-v2
spec:
  type: ClusterIP # ClusterIP, # NodePort # LoadBalancer
  selector:
    app: myapp1-v2
  ports: 
    - name: http
      port: 80 # Service Port
      targetPort: 80 # Container Port

Step-02-09: c4-03-gateway-app1-http-route.yaml¶

kind: HTTPRoute
apiVersion: gateway.networking.k8s.io/v1
metadata:
  name: app1-route
spec:
  parentRefs:
  - kind: Gateway
    name: mygateway1-regional
    sectionName: https
  rules:
  - backendRefs:
    - name: myapp1-service-v1
      port: 80
      weight: 50
    - name: myapp1-service-v2
      port: 80
      weight: 50

Step-02-10: Deploy and Verify Resources¶

# List Kubernetes Gateway Classes
kubectl get gatewayclass

# Deploy Kubernetes Resources
kubectl apply -f p2-regional-k8sresources-yaml

# List Kubernetes Deployments
kubectl get deploy

# List Kubernetes Pods
kubectl get pods

# List Kubernetes Services
kubectl get svc

# List Kubernetes Gateways created using Gateway API
kubectl get gateway
kubectl get gtw

# Describe Gateway
kubectl describe gateway mygateway1-regional

# List HTTP Route
kubectl get httproute

# Verify Gateway is GCP GKE Console
Go to GKE Console -> Networking -> Gateways, Services & Ingress -> mygateway1-regional

# Verify GCP Cloud Load Balancer
Go to Cloud Load Balancers -> Review load balancer settings

# Host Entry
35.208.69.211 app1.stacksimplify.com

# Access Application
http://<DNS-URL> should redirect to https://<DNS-URL>
Observation:
1. Requests should be split between V1 and V2 version

Step-02-11: Clean-up¶

# Delete Kubernetes Resources
kubectl delete -f p2-regional-k8sresources-yaml

Step-03: Project-3: p3-k8sresources-terraform-manifests: Terraform Manifests¶

Step-03-01: NO changes to following manifests¶

Folder: p3-k8sresources-terraform-manifests
c2-01-variables.tf
c2-02-local-values.tf
c3-01-remote-state-datasource.tf
c3-02-providers.tf
c5-01-gateway.tf
c5-02-gateway-http-to-https-route.tf
c6-static-ip.tf
c7-certificate-manager.tf
terraform.tfvars

Step-03-02: c1-versions.tf¶

Update your Cloud Storage Bucket

  backend "gcs" {
    bucket = "terraform-on-gcp-gke"
    prefix = "dev/k8s-gateway-regional-demo1"    
  }

Step-03-03: Review MyApp1 V1 and V2 versions¶

c4-01-myapp1-v1-deployment.tf
c4-02-myapp1-v1-clusterip-service.tf
c4-03-myapp2-v2-deployment.tf
c4-04-myapp2-v2-clusterip-service.tf

Step-03-04: c5-03-gateway-app1-http-route.tf¶

resource "kubernetes_manifest" "app1_http_route" {
  manifest = {
    apiVersion = "gateway.networking.k8s.io/v1"
    kind       = "HTTPRoute"
    metadata = {
      name = "app1-route"
      namespace = "default"      
    }
    spec = {
      parentRefs = [{
        kind = "Gateway"
        name = "mygateway1-regional"
        sectionName = "https"
      }]
      rules = [        
        {
          backendRefs = [
            {
              name = kubernetes_service_v1.myapp1_service_v1.metadata[0].name 
              port = 80
              weight = 50
            },
            {
              name = kubernetes_service_v1.myapp1_service_v2.metadata[0].name 
              port = 80
              weight = 50              
            }            
          ]
        }        
      ]      
    }
  }
}

Step-03-05: Execute Terraform Commands¶

# Change Directory
cd p3-regional-k8sresources-terraform-manifests

# Terraform Initialize
terraform init

# Terraform Validate
terraform validate

# Terraform plan
terraform plan

# Terraform Apply
terraform apply -auto-approve

Step-03-06: Verify Kubernetes Resources¶

# List Kubernetes Deployments
kubectl get deploy

# List Kubernetes Pods
kubectl get pods

# List Kubernetes Services
kubectl get svc

# List Kubernetes Gateways created using Gateway API
kubectl get gateway
kubectl get gtw

# Describe Gateway
kubectl describe gateway mygateway1-regional

# List HTTP Route
kubectl get httproute

# Verify Gateway is GCP GKE Console
Go to GKE Console -> Networking -> Gateways, Services & Ingress -> mygateway1-regional

# Verify GCP Cloud Load Balancer
Go to Cloud Load Balancers -> Review load balancer settings

# Verify Certificate Manager SSL Certificate
Go to Cloud Certificate Manager

# Host Entry
35.208.69.211 app1.stacksimplify.com

# Access Application
http://<DNS-URL> should redirect to https://<DNS-URL>
Observation:
1. Requests should be split between V1 and V2 version

Step-03-07: Clean-Up¶

# Change Directory
cd p3-regional-k8sresources-terraform-manifests

# Terraform Destroy
terraform apply -destroy -auto-approve

Gateway Documentation¶

https://gateway-api.sigs.k8s.io/reference/spec/#gateway.networking.k8s.io/v1.Listener