About service mesh

A service mesh is a dedicated infrastructure layer that you add your apps to, which ensures secure service-to-service communication across cloud networks. With a service mesh, you can solve problems such as service identity, mutual TLS communication, consistent L7 network telemetry gathering, service resilience, secure traffic routing between services across clusters, and policy enforcement, such as to enforce quotas or rate limit requests. To learn more about the benefits of using a service mesh, see What is a service mesh in the Gloo Mesh Enterprise documentation.

About Istio

The open source project Istio is the leading service mesh implementation that offers powerful features to secure, control, connect, and monitor cloud-native, distributed applications. Istio is designed for workloads that run in one or more Kubernetes clusters, but you can also extend your service mesh to include virtual machines and other endpoints that are hosted outside your cluster. The key benefits of Istio include:

  • Automatic load balancing for HTTP, gRPC, WebSocket, MongoDB, and TCP traffic
  • Secure TLS encryption for service-to-service communication with identity-based authentication and authorization
  • Advanced routing and traffic management policies, such as retries, failovers, and fault injection
  • Fine-grained access control and quotas
  • Automatic logs, metrics, and traces for traffic in the service mesh

About the Gloo Gateway Istio integration

Gloo Gateway comes with an Istio integration that allows you to configure your gateway proxy with an Istio sidecar. The Istio sidecar uses mutual TLS (mTLS) to prove its identity and to secure the connection between your gateway and the services in your Istio service mesh. In addition, you can control and secure the traffic that enters the mesh by applying all the advanced routing, traffic management, security, resiliency, and AI capabilities that Gloo Gateway offers. For example, you can set up end-user authentication and authorization, per-user rate limiting quotas, web application filters, and access logging to help prevent malicious attacks and audit service mesh usage.

Before you begin

  1. Follow the Get started guide to install Gloo Gateway, set up a gateway resource, and deploy the httpbin sample app.

  2. Get the external address of the gateway and save it in an environment variable.

      export INGRESS_GW_ADDRESS=$(kubectl get svc -n gloo-system gloo-proxy-http -o jsonpath="{.status.loadBalancer.ingress[0]['hostname','ip']}")
echo $INGRESS_GW_ADDRESS  
  
      kubectl port-forward deployment/gloo-proxy-http -n gloo-system 8080:8080

Set up an Istio service mesh

Use Solo.io’s Gloo Mesh Enterprise product to install a managed Istio version by using the built-in Istio lifecycle manager, or manually install and manage your own Istio installation.

Gloo Mesh Enterprise is a service mesh management plane that is based on hardened, open-source projects like Envoy and Istio. With Gloo Mesh, you can unify the configuration, operation, and visibility of service-to-service connectivity across your distributed applications. These apps can run in different virtual machines (VMs) or Kubernetes clusters on premises or in various cloud providers, and even in different service meshes.

Follow the Gloo Mesh Enterprise get started guide to quickly install a managed Solo distribution of Istio by using the built-in Istio lifecycle manager.

Set up Istio. Choose between the following options to set up Istio:

Enable the Istio integration in Gloo Gateway

Upgrade your Gloo Gateway installation to enable the Istio integration.

  1. Get the name of the istiod service. Depending on how you set up Istio, you might see a revisionless service name (istiod) or a service name with a revision, such as istiod-1-21.

      kubectl get services -n istio-system

    Example output:

      NAME          TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)                                 AGE
istiod-1-21   ClusterIP   10.102.24.31   <none>        15010/TCP,15012/TCP,443/TCP,15014/TCP   3h49m

  2. Derive the Kubernetes service address for your istiod deployment. The service address uses the format <service-name>.<namespace>.svc:15012. For example, if your service name is istiod-1-21, the full service address is istiod-1-21.istio-system.svc:15012.

  3. Get the Helm values for your current Gloo Gateway installation.

      helm get values gloo-gateway -n gloo-system -o yaml > gloo-gateway.yaml
open gloo-gateway.yaml

  4. Add the following values to the Helm value file. Make sure that you change the istioProxyContainer values to the service address and cluster name of your Istio installation.

      
global:
  istioIntegration:
    enableAutoMtls: true
    enabled: true
  istioSDS:
    enabled: true
kubeGateway:
  enabled: true
  gatewayParameters:
    glooGateway:
      istio:
        istioProxyContainer: 
          istioDiscoveryAddress: istiod-1-21.istio-system.svc:15012
          istioMetaClusterId: mycluster
          istioMetaMeshId: mycluster
  
      
global:
  istioIntegration:
    enableAutoMtls: true
    enabled: true
  istioSDS:
    enabled: true
gloo: 
  kubeGateway:
    enabled: true
    gatewayParameters:
      glooGateway:
        istio:
          istioProxyContainer: 
            istioDiscoveryAddress: istiod-1-21.istio-system.svc:15012
            istioMetaClusterId: mycluster
            istioMetaMeshId: mycluster

    SettingDescription
    istioDiscoveryAddressThe address of the istiod service. If omitted, istiod.istio-system.svc:15012 is used.
    istioMetaClusterId
    istioMetaMeshId    		The name of the cluster where Gloo Gateway is installed.

  5. Upgrade your Gloo Gateway installation.

      helm upgrade -n gloo-system gloo-gateway gloo/gloo \
   -f gloo-gateway.yaml \
   --version=1.18.0-beta34
  
      helm upgrade -n gloo-system gloo-gateway glooe/gloo-ee \
 -f gloo-gateway.yaml \
 --version=1.18.0-beta2

  6. Verify that your gloo-proxy-http pod is restarted with 3 containers now: gateway-proxy, istio-proxy, and sds.

      kubectl get pods -n gloo-system | grep gloo-proxy-http

    Example output:

      gloo-proxy-http-f7cd596b7-tv5z7    3/3     Running            0              3h31m

  7. Optional: Review the GatewayParameters resource and verify that the istioDiscoveryAddress, istioMetaClusterId, and istioMetaMeshId are set to the values from your Helm chart.

      kubectl get gatewayparameters gloo-gateway -n gloo-system -o yaml

    Example output:

       apiVersion: gateway.gloo.solo.io/v1alpha1
   kind: GatewayParameters
   metadata:
     annotations:
       meta.helm.sh/release-name: gloo-gateway
       meta.helm.sh/release-namespace: gloo-system
   ...
   spec:
     kube:
       deployment:
         replicas: 1
       ...
       istio:
         istioProxyContainer:
           image:
             pullPolicy: IfNotPresent
             registry: docker.io/istio
             repository: proxyv2
             tag: 1.22.0
           istioDiscoveryAddress: istiod-1-21.istio-system.svc:15012
           istioMetaClusterId: mycluster
           istioMetaMeshId: mycluster
           logLevel: warning
        podTemplate:
         extraLabels:
           gloo: kube-gateway
   ...

  8. Optional: Review the Settings resource and verify that appendXForwardedHost, enableAutoMtls, and enableIntegration are all set to true.

      kubectl get settings default -n gloo-system -o yaml

    Example output:

       apiVersion: gloo.solo.io/v1
   kind: Settings
   metadata:
     annotations:
       meta.helm.sh/release-name: gloo-gateway
       meta.helm.sh/release-namespace: gloo-system
   spec:
     consoleOptions:
       apiExplorerEnabled: true
       readOnly: false
     discovery:
       fdsMode: WHITELIST
     discoveryNamespace: gloo-system
     gloo:
       ...
       istioOptions:
         appendXForwardedHost: true
         enableAutoMtls: true
         enableIntegration: true
   ...

Set up mTLS routing to httpbin

  1. Label the httpbin namespace for Istio sidecar injection.

      export REVISION=$(kubectl get pod -L app=istiod -n istio-system -o jsonpath='{.items[0].metadata.labels.istio\.io/rev}')      
echo $REVISION
kubectl label ns httpbin istio.io/rev=$REVISION --overwrite=true

  2. Perform a rollout restart for the httpbin deployment so that an Istio sidecar is automatically added to the httpbin app.

      kubectl rollout restart deployment httpbin -n httpbin

  3. Verify that the httpbin app comes up with a fourth container.

      kubectl get pods -n httpbin

    Example output:

      NAME                      READY   STATUS    RESTARTS   AGE
httpbin-f46cc8b9b-f4wbm   4/4     Running   0          10s

  4. Send a request to the httpbin app. Verify that you get back a 200 HTTP response and that an x-forwarded-client-cert header is returned. The presence of this header indicates that the connection from the gateway to the httpbin app is now encrypted with mutual TLS.

      curl -vik http://$INGRESS_GW_ADDRESS:8080/headers -H "host: www.example.com:8080"
  
      curl -vik localhost:8080/headers -H "host: www.example.com"

    Example output:

       {
    "headers": {
      "Accept": [
        "*/*"
      ],
      "Host": [
        "www.example.com:8080"
      ],
      "User-Agent": [
        "curl/7.77.0"
      ],
      "X-B3-Sampled": [
        "0"
      ],
      "X-B3-Spanid": [
        "92744e97e79d8f22"
      ],
      "X-B3-Traceid": [
        "8189f0a6c4e3582792744e97e79d8f22"
      ],
      "X-Forwarded-Client-Cert": [
        "By=spiffe://gloo-edge-docs-mgt/ns/httpbin/sa/httpbin;Hash=3a57f9d8fddea59614b4ade84fcc186edeffb47794c06608068a3553e811bdfe;Subject=\"\";URI=spiffe://gloo-edge-docs-mgt/ns/gloo-system/sa/gloo-proxy-http"
      ],
      "X-Forwarded-Proto": [
        "http"
      ],
      "X-Request-Id": [
        "7f1d6e38-3bf7-44fd-8298-a77c34e5b865"
      ]
    }
   }

Exclude a service from mTLS

You can exclude a service from requiring to communicate with the gateway proxy via mTLS by adding the disableIstioAutoMtls option to the Upstream that represents your service.

  1. Create an Upstream resource that represents the httpbin app and add the disableIstioAutoMtls: true option to it. This option excludes the httpbin Upstream from communicating with the gateway proxy via mTLS.

      kubectl apply -f- <<EOF
apiVersion: gloo.solo.io/v1
kind: Upstream
metadata:
  name: httpbin
  namespace: gloo-system
spec:
  disableIstioAutoMtls: true
  kube:
    serviceName: httpbin
    serviceNamespace: httpbin
    servicePort: 8000
EOF

  2. Create an HTTPRoute resource that routes traffic to the httpbin Upstream that you created.

      kubectl apply -f- <<EOF
apiVersion: gateway.networking.k8s.io/v1beta1
kind: HTTPRoute
metadata:
  name: exclude-automtls
  namespace: gloo-system
spec:
  parentRefs:
  - name: http
    namespace: gloo-system
  hostnames:
    - disable-automtls.example
  rules:
    - backendRefs:
      - name: httpbin
        kind: Upstream
        group: gloo.solo.io
EOF

  3. Send a request to the httpbin app on the disable-automtls.example domain. Verify that you do not get back the x-forwarded-client-cert header.

      curl -vik http://$INGRESS_GW_ADDRESS:8080/headers \
 -H "host:disable-automtls.example:8080"
  
      curl -vik localhost:8080/headers 
 -H "host: disable-automtls.example"

    Example output:

      {
  "headers": {
     "Accept": [
      "*/*"
    ],
    "Host": [
      "disable-automtls.example:8080"
    ],
     "User-Agent": [
       "curl/7.77.0"
     ],
     "X-Forwarded-Proto": [
      "http"
     ],
    "X-Request-Id": [
      "47c4dcc8-551b-4c93-8aa3-1cd1e15b137c"
    ]
  }
}

  4. Repeat the request to the httpbin app on the www.example.com domain that is enabled for mTLS. Verify that you continue to see the x-forwarded-client-cert header.

      curl -vik http://$INGRESS_GW_ADDRESS:8080/headers \
 -H "host: www.example.com:8080"
  
      curl -vik localhost:8080/headers 
 -H "host: www.example.com"

    Example output:

       {
    "headers": {
      "Accept": [
        "*/*"
      ],
      "Host": [
        "www.example.com:8080"
      ],
      "User-Agent": [
        "curl/7.77.0"
      ],
      "X-Forwarded-Client-Cert": [
        "By=spiffe://gloo-edge-docs-mgt/ns/httpbin/sa/httpbin;Hash=3a57f9d8fddea59614b4ade84fcc186edeffb47794c06608068a3553e811bdfe;Subject=\"\";URI=spiffe://gloo-edge-docs-mgt/ns/gloo-system/sa/gloo-proxy-http"
      ],
      "X-Forwarded-Proto": [
        "http"
      ],
      "X-Request-Id": [
        "7f1d6e38-3bf7-44fd-8298-a77c34e5b865"
      ]
    }
   }

Cleanup

You can optionally remove the resources that you created.

  1. Follow the Uninstall guide in the Gloo Mesh Enterprise documentation to remove Gloo Mesh Enterprise.

  2. Follow the upgrade guide to upgrade your Gloo Gateway Helm installation values. Remove the Helm values that you added as part of this guide.

  3. Remove the Istio sidecar from the httpbin app.

    1. Remove the Istio label from the httpbin namespace.

        kubectl label ns httpbin istio.io/rev-

    2. Perform a rollout restart for the httpbin deployment.

        kubectl rollout restart deployment httpbin -n httpbin

    3. Verify that the Istio sidecar container is removed.

        kubectl get pods -n httpbin

      Example output:

        NAME                       READY   STATUS        RESTARTS   AGE
httpbin-7d4965fb6d-mslx2   3/3     Running       0          6s

  4. Remove the Upstream and HTTPRoute that you used to exclude a service from mTLS.

      kubectl delete upstream httpbin -n gloo-system
kubectl delete httproute exclude-automtls -n gloo-system