Install Istio in Dual-Stack mode

Prerequisites

Installation steps

If you want to use kind for your test, you can set up a dual stack cluster with the following command:

$ kind create cluster --name istio-ds --config - <<EOF
kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
networking:
  ipFamily: dual
EOF

To enable dual-stack for Istio, you will need to modify your IstioOperator or Helm values with the following configuration.

apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
spec:
  meshConfig:
    defaultConfig:
      proxyMetadata:
        ISTIO_DUAL_STACK: "true"
  values:
    pilot:
      env:
        ISTIO_DUAL_STACK: "true"
    # The below values are optional and can be used based on your requirements
    gateways:
      istio-ingressgateway:
        ipFamilyPolicy: RequireDualStack
      istio-egressgateway:
        ipFamilyPolicy: RequireDualStack

Verification

  1. Create three namespaces:

    • dual-stack: tcp-echo will listen on both an IPv4 and IPv6 address.
    • ipv4: tcp-echo will listen on only an IPv4 address.
    • ipv6: tcp-echo will listen on only an IPv6 address.
    $ kubectl create namespace dual-stack
    $ kubectl create namespace ipv4
    $ kubectl create namespace ipv6
    
  2. Enable sidecar injection on all of those namespaces as well as the default namespace:

    $ kubectl label --overwrite namespace default istio-injection=enabled
    $ kubectl label --overwrite namespace dual-stack istio-injection=enabled
    $ kubectl label --overwrite namespace ipv4 istio-injection=enabled
    $ kubectl label --overwrite namespace ipv6 istio-injection=enabled
    
  3. Create tcp-echo deployments in the namespaces:

    $ kubectl apply --namespace dual-stack -f @samples/tcp-echo/tcp-echo-dual-stack.yaml
    $ kubectl apply --namespace ipv4 -f @samples/tcp-echo/tcp-echo-ipv4.yaml
    $ kubectl apply --namespace ipv6 -f @samples/tcp-echo/tcp-echo-ipv6.yaml
    
  4. Apply the sleep deployment in the default namespace:

    $ kubectl apply -f @samples/sleep/sleep.yaml
    
  5. Verify the traffic reaches the pods:

    $ kubectl exec -it "$(kubectl get pod -l app=sleep -o jsonpath='{.items[0].metadata.name}')" -- sh -c "echo dualstack | nc tcp-echo.dual-stack 9000"
    hello dualstack
    $ kubectl exec -it "$(kubectl get pod -l app=sleep -o jsonpath='{.items[0].metadata.name}')" -- sh -c "echo ipv4 | nc tcp-echo.ipv4 9000"
    hello ipv4
    $ kubectl exec -it "$(kubectl get pod -l app=sleep -o jsonpath='{.items[0].metadata.name}')" -- sh -c "echo ipv6 | nc tcp-echo.ipv6 9000"
    hello ipv6
    
  6. Verify the envoy listeners:

    $ istioctl proxy-config listeners "$(kubectl get pod -n dual-stack -l app=tcp-echo -o jsonpath='{.items[0].metadata.name}')" -n dual-stack --port 9000
    

    You will see listeners are now bound to multiple addresses, but only for dual stack services. Other services will only be listening on a single IP address.

    "name": "fd00:10:96::f9fc_9000",
    "address": {
        "socketAddress": {
            "address": "fd00:10:96::f9fc",
            "portValue": 9000
        }
    },
    "additionalAddresses": [
        {
            "address": {
                "socketAddress": {
                    "address": "10.96.106.11",
                    "portValue": 9000
                }
            }
        }
    ],
    
  7. Verify virtual inbound addresses are configured to listen on both 0.0.0.0 and [::].

    "name": "virtualInbound",
    "address": {
        "socketAddress": {
            "address": "0.0.0.0",
            "portValue": 15006
        }
    },
    "additionalAddresses": [
        {
            "address": {
                "socketAddress": {
                    "address": "::",
                    "portValue": 15006
                }
            }
        }
    ],
    
  8. Verify envoy endpoints are configured to route to both IPv4 and IPv6:

    $ istioctl proxy-config endpoints "$(kubectl get pod -l app=sleep -o jsonpath='{.items[0].metadata.name}')" --port 9000
    ENDPOINT                 STATUS      OUTLIER CHECK     CLUSTER
    10.244.0.19:9000         HEALTHY     OK                outbound|9000||tcp-echo.ipv4.svc.cluster.local
    10.244.0.26:9000         HEALTHY     OK                outbound|9000||tcp-echo.dual-stack.svc.cluster.local
    fd00:10:244::1a:9000     HEALTHY     OK                outbound|9000||tcp-echo.dual-stack.svc.cluster.local
    fd00:10:244::18:9000     HEALTHY     OK                outbound|9000||tcp-echo.ipv6.svc.cluster.local
    

Now you can experiment with dual-stack services in your environment!

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