Set up an ingress gateway

This guide demonstrates how to configure Traffic Director to configure proxies as ingress gateways. You set up an Envoy proxy as the gateway and a hello-world in-mesh service.

In this configuration, an external passthrough Network Load Balancer directs traffic from the internet to your service mesh through an ingress gateway. A Gateway resource manages an Envoy proxy that acts as a gateway into the service mesh. A gateway is also known as a middle proxy or ingress. The Envoy proxies deployed to act as ingress gateways are standalone proxies rather than a sidecar to a workload. In this mode, Envoy listens on a defined list of ports, and forwards traffic according to routing rules that you configure in Traffic Director. A new Gateway API resource is used to configure such Envoy proxies.

Envoy proxy as ingress gateway, with external passthrough Network Load Balancer, and Gateway resource (click to enlarge)

Set up routing to ensure that traffic destined for the Gateway proxies is directed to the VMs hosting the Envoys. The ingress service can be paired with an external Application Load Balancer or an internal passthrough Network Load Balancer, but such configurations are not included in this demonstration setup. For information about setting up an external Application Load Balancer, see the External Application Load Balancer documentation. For information about setting up an internal passthrough Network Load Balancer, see the Internal passthrough Network Load Balancer documentation.

This guide does not cover the service-to-service communication and the Mesh resource behind the Gateway.

Before you begin

Make sure that your deployment meets the prerequisites described in the following guides:

• Prepare to set up Traffic Director with Envoy
• Traffic Director service routing setup guides

Configure firewall rules

In this section, you configure two firewall rules. One rule allows health check probes to access instances in the Virtual Private Cloud network. The other rule allows traffic from any source into the network.

1. Configure firewall rules to allow health checks.

   gcloud compute firewall-rules create allow-health-checks \
     --network=NETWORK_NAME \
     --direction=INGRESS \
     --action=ALLOW \
     --rules=tcp \
     --source-ranges="35.191.0.0/16,130.211.0.0/22,209.85.152.0/22,209.85.204.0/22"
   

2. Configure firewall rules to allow traffic from any source on the internet to reach the gateway proxies. You can optionally edit the command for your source IP address range.

   gcloud compute firewall-rules create allow-gateway-ingress-traffic \
     --network=NETWORK_NAME \
     --direction=INGRESS \
     --action=ALLOW \
     --rules=tcp:80 \
     --source-ranges="0.0.0.0/0" \
     --target-tags=gateway-proxy
   

Configure Identity and Access Management permissions

In this section, you designate the service account for the gateway proxies and assign them the correct IAM roles.

1. Create a service account identity for the gateway proxies.

   gcloud iam service-accounts create gateway-proxy
   

2. Assign the required IAM roles to the service account identity.

   gcloud projects add-iam-policy-binding PROJECT_ID \
     --member="serviceAccount:gateway-proxy@PROJECT_ID.iam.gserviceaccount.com" \
     --role="roles/trafficdirector.client"
   

   gcloud projects add-iam-policy-binding PROJECT_ID \
     --member="serviceAccount:gateway-proxy@PROJECT_ID.iam.gserviceaccount.com" \
     --role="roles/logging.logWriter"
   

Configure the Gateway resource

In this section, you configure the gateway resource.

1. In a file called gateway80.yaml, create the Gateway specification for HTTP traffic.

   cat <<EOF | tee gateway80.yaml
   name: gateway80
   scope: gateway-proxy
   ports:
   - 80
   type: OPEN_MESH
   EOF
   

2. Create the Gateway resource from the gateway80.yaml specification:

   gcloud network-services gateways import gateway80 \
     --source=gateway80.yaml \
     --location=global
   

Create a managed instance group with Envoy proxies

In this section, you create the Envoy proxies that are associated with the ingress gateway configuration.

1. Create an instance template for a VM running an automatically deployed Envoy service proxy. The Envoys have a scope of gateway-proxy. Do not pass the serving port as a parameter of --service-proxy.

   gcloud beta compute instance-templates create gateway-proxy \
     --machine-type=n1-standard-1 \
     --boot-disk-size=10GB \
     --scopes=https://www.googleapis.com/auth/cloud-platform \
     --tags=gateway-proxy \
     --network=NETWORK_NAME \
     --service-account="gateway-proxy@PROJECT_ID.iam.gserviceaccount.com" \
     --service-proxy=enabled,scope=gateway-proxy
   

2. Create a regional managed instance group from the instance template.

   gcloud compute instance-groups managed create gateway-proxies-REGION \
     --region=REGION \
     --size=3 \
     --template=gateway-proxy \
     --target-distribution-shape=EVEN
   

3. Set a named port to enable TCP health checking for the external passthrough Network Load Balancer.

   gcloud compute instance-groups managed set-named-ports gateway-proxies-REGION \
     --region=REGION \
     --named-ports=serving-port:80
   

Set up the regional external passthrough Network Load Balancer

In this section, you create the external passthrough Network Load Balancer, a backend service forwarding rule, and required health check, to forward traffic from the internet to the gateway proxies.

1. Create an external IP address for the external passthrough Network Load Balancer.

   gcloud compute addresses create xnlb-REGION \
     --region=REGION
   

2. Get the IP address that was created for the external passthrough Network Load Balancer.

   gcloud compute addresses describe xnlb-REGION \
     --region=REGION --format='value(address)'
   

   This IP address is used as the variable IP_ADDRESS in later sections of this setup guide.

3. Create a health check for the gateway proxies.

   gcloud compute health-checks create tcp xnlb-REGION \
     --region=REGION \
     --port-name=serving-port
   

4. Create a backend service for the gateway proxies.

   gcloud compute backend-services create xnlb-REGION \
     --health-checks=xnlb-REGION \
     --health-checks-region=REGION \
     --load-balancing-scheme=EXTERNAL \
     --protocol=TCP \
     --region=REGION \
     --port-name=serving-port
   

5. Add the managed instance group as the backend to the backend service.

   gcloud compute backend-services add-backend xnlb-REGION \
     --instance-group=gateway-proxies-REGION \
     --instance-group-region=REGION \
     --region=REGION
   

6. Create a forwarding rule pointing to the gateway proxies.

   gcloud compute forwarding-rules create xnlb-REGION \
     --region=REGION \
     --load-balancing-scheme=EXTERNAL \
     --address=IP_ADDRESS \
     --ip-protocol=TCP \
     --ports=80 \
     --backend-service=xnlb-REGION \
     --backend-service-region=REGION
   

Configure the HTTP server

In this section, you create a hello-world HTTP test service running in the service mesh that gateway proxies are routing into.

1. Create an instance template running an Apache web server, serving the instance's hostname as it responds to HTTP requests.

   gcloud compute instance-templates create helloworld-template \
     --scopes=https://www.googleapis.com/auth/cloud-platform \
     --tags=private-instance \
     --image-family=debian-11 \
     --image-project=debian-cloud \
     --network=NETWORK_NAME \
     --metadata=startup-script="#! /bin/bash
   
   sudo apt-get update -y
   sudo apt-get install apache2 -y
   echo \"Hello from \`/bin/hostname\`\" | sudo tee /var/www/html/index.html
   sudo service apache2 restart"
   

2. Create a managed instance group based on the template.

   gcloud compute instance-groups managed create helloworld-mig-REGION \
     --zone=ZONE \
     --size=1 \
     --template=helloworld-template
   

3. Create an HTTP health check.

   gcloud compute health-checks create http helloworld-health-check
   

4. Create a firewall rule to allow incoming connections from gateway proxies and health checks to instances in your network.

   gcloud compute firewall-rules create allow-rfc1918-traffic \
      --network=NETWORK_NAME \
      --action=allow \
      --direction=INGRESS \
      --source-ranges=10.0.0.0/8,172.16.0.0/12,192.168.0.0/16 \
      --target-tags=private-instance \
      --rules=tcp:80
   

5. Create a global backend service with a load balancing scheme of INTERNAL_SELF_MANAGED and attach the health check.

   gcloud compute backend-services create http-helloworld-service \
     --load-balancing-scheme=INTERNAL_SELF_MANAGED \
     --protocol=HTTP \
     --health-checks=helloworld-health-check \
     --global
   

6. Add the managed instance group to the backend service.

   gcloud compute backend-services add-backend http-helloworld-service \
     --instance-group helloworld-mig-REGION \
     --instance-group-zone=ZONE \
     --global
   

Set up routing with HTTPRoute

You now have a Traffic Director Gateway resource and a service configured. Next, you connect them by using an HTTPRoute resource that associates a hostname with a backend service. The HTTPRoute also references the Gateway.

1. In a file called http_route.yaml, create the HTTPRoute specification. The specification references gateway80, which is the Gateway resource that you created earlier, and it points to the backend service http-helloworld-service.

   You can use either PROJECT_ID or PROJECT_NUMBER.

   cat <<EOF | tee http_route.yaml
   name: helloworld-http-route
   hostnames:
   - helloworld-gce
   gateways:
   - projects/PROJECT_NUMBER/locations/global/gateways/gateway80
   rules:
   - action:
       destinations:
       - serviceName: "projects/PROJECT_NUMBER/locations/global/backendServices/http-helloworld-service"
   EOF
   

2. Use the specification in http_route.yaml to create the HTTPRoute resource.

   gcloud network-services http-routes import helloworld-http-route \
     --source=http_route.yaml \
     --location=global
   

3. Verify that you can access the service from an external client through the external passthrough Network Load Balancer and the Traffic Director Gateway.

   curl -H "Host: helloworld-gce" IP_ADDRESS