Here’s How to Use Istio with Other Nginx Ingress Proxies

Can I Use Istio with Other Ingress Proxies?

It’s been a common problem that we’ve been asked to address, and something that pops up frequently. Can I use Istio with other ingress proxies? In a word? Yes.

A persistent issue for many engineers wanting to adopt Istio has been that they want to make use of the numerous benefits that it can provide, including its ability to solve telemetry issues, security and transport problems, as well as policy concerns all in one place, but redesigning their entire service to fit with their hopes for the mesh, they need aspects of the mesh to fit in with them.

In this case it’s specific to mutual TLS (mTLS), to make use of the encrypted communications/ security it provides between apps. mTLS requires both sides to prove their identity, and therefore provides increased security so it’s no surprise that engineers want to use it. But, if there are already established Ingress Proxies, for example NGINX or HAProxy, that they wish to keep without provisioning their ingress certificates from Citadel (which, while customizable in many ways, Citadel has yet to provide an easy way to do this specifically), but it can be done.

Tetrate offers enterprise-ready, 100% upstream distributions of Istio and Envoy Gateway, the easiest way to implement mTLS for cloud-native applications. Get access now ›

Three Common Ways to Deploy NGINX Proxy in an Istio Service Mesh

1. Use dedicated ingress instances per team (in Kubernetes, a set of ingress instances per namespace)
2. Use a set of ingress instances shared across several teams (namespaces)
3. Use a mix, where a team has a dedicated ingress that spans multiple namespaces

The most common method is to run the ingress proxy with an Istio sidecar, which can handle certificates/identity from Citadel and perform mTLS into the mesh.

There’s a lot of confusion about how to configure this properly, but it can actually be done simply. What set configuration you need depends on how your ingress is deployed. There are three common ways in which ingress proxies are deployed in Kubernetes. The first is running dedicated ingress instances per team (in Kubernetes, a set of ingress instances per namespace). The second is a set of ingress instances shared across several teams (namespaces). The third is a mix, where a team has a dedicated ingress that spans multiple namespaces they own, or the organization has a mix of teams with dedicated ingress and teams that use a shared ingress, or a mix of all of the above. These three cases reduce to two scenarios we’ll need to configure in Istio:

×

No matter what architecture the ingress is deployed with, we’re going to use the same set of tools to solve the problem. We need to:

Deployment Pattern: Use Dedicated Ingress Instances per Team

Deploy the ingress proxy with an Envoy sidecar. Annotate ingress deployment with:

sidecar.istio.io/inject: 'true'

Exempt inbound traffic from going through the sidecar, since we want the ingress proxy to handle it.Annotate the deployment with:

traffic.sidecar.istio.io/includeInboundPorts: ""
traffic.sidecar.istio.io/excludeInboundPorts: "80,443"

Note: substitute the ports your ingress is exposing in your own deployment.

If your ingress proxy needs to talk to the Kubernetes API server (e.g. because the ingress controller is embedded into the ingress pod, like with NGINX ingress) then you’ll need to allow it to call the Kubernetes API server without the sidecar interfering.Annotate the deployment with:

traffic.sidecar.istio.io/excludeOutboundIPRanges: "1.1.1.1/24,2.2.2.2/16,3.3.3.3/20"

Note: substitute your own Kubernetes API server IP ranges. You can find the IP address by:

kubectl get svc kubernetes -o jsonpath='{.spec.clusterIP}'

Instead of routing the outbound traffic to the list of endpoints in the NGINX upstream configuration, you should configure the nginx ingress to route to a single upstream service, so that the outbound traffic will be intercepted by the istio sidecar. Add the following annotation to each Ingress resource:

kubernetes.io/ingress.class: nginx
nginx.ingress.kubernetes.io/service-upstream: "true"
nginx.ingress.kubernetes.io/upstream-vhost: httpbin.default.svc.cluster.local

Configure the ingress’s sidecar to route traffic to services in the mesh. This is the key piece that changes per deployment type.For ingresses in the same namespace as services they’re forwarding traffic to, no extra configuration is required. A sidecar in a namespace automatically knows how to route traffic to services in the same namespace.For ingresses in a namespace different from the services they’re forwarding traffic to, you need to author an Istio Sidecar API object in the ingress’s namespace which allows Egress to the services your ingress is routing to.

apiVersion: networking.istio.io/v1alpha3
kind: Sidecar
metadata:
  name: ingress
  namespace: ingress-namespace
spec:
  egress:
  - hosts:
    # only the frontend service in the prod-us1 namespace
    - "prod-us1/frontend.prod-us1.svc.cluster.local"
    # any service in the prod-apis namespace
    - "prod-apis/\*"
    # tripping hazard: make sure you include istio-system!
    - "istio-system/\*"

Note: Substitute the services/namespaces your ingress is sending traffic to. Make sure to always include “istio-system/*” or the sidecar won’t be able to talk to the control plane. (This is a temporary requirement as of 1.4.x that should be fixed in future versions of Istio.)

After applying all the configs to Kubernetes (see the full example below) we have a deployment pictured below. We can use curl connect to services in the cluster to verify traffic flows through Envoy and mTLS is enforced.

×

Deployment Pattern: Use Ingress Instances Shared across Several Teams

curl via the ingress in the same namespace as the app:

curl $(kubectl get svc -n default ingress-nginx -o jsonpath='{.status.loadBalancer.ingress[0].ip}')/ip -v

curl via the ingress in a different namespace than the app:

curl $(kubectl get svc -n ingress ingress-nginx -o jsonpath='{.status.loadBalancer.ingress[0].ip}')/ip -v

curl via a pod in another namespace that does not have a sidecar:

kubectl exec -it$(kubectl get pod -n legacy -l app=sleep -o
jsonpath='{.items[0].metadata.name}') -n legacy -- curl httpbin.default.svc.cluster.local:8000/ip -v

Deployment Pattern: Dedicated Ingress that Spans Multiple Namespaces

Create cluster:

gcloud container clusters create -m n1-standard-2 ingress-test

Download istio 1.4.2

export ISTIO_VERSION=1.4.2; curl -L https://istio.io/downloadIstio | sh -

Deploy Istio (demo deployment with mTLS):

./istio-1.4.2/bin/istioctl manifest apply \
	--set values.global.mtls.enabled=true \
	--set values.global.controlPlaneSecurityEnabled=true

Label default namespace for automatic sidecar injection, deploy httpbin:

kubectl label namespace default istio-injection=enabled
kubectl apply -f ./istio-1.4.2/samples/httpbin/httpbin.yaml

Deploy NGINX ingress controller and config into default namespace:

export KUBE_API_SERVER_IP=$(kubectl get svc kubernetes -o jsonpath='{.spec.clusterIP}')/32
sed "s#__KUBE_API_SERVER_IP__#${KUBE_API_SERVER_IP}#" nginx-default-ns.yaml | kubectl apply -f -

This is the nginx configuration:

\# nginx-default-ns.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: nginx-ingress
  namespace: default
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/service-upstream: "true"
    nginx.ingress.kubernetes.io/upstream-vhost: httpbin.default.svc.cluster.local
spec:
  backend:
    serviceName: httpbin
    servicePort: 8000
---
# Deployment: nginx-ingress-controller
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-ingress-controller
  namespace: default
spec:
  replicas: 1
  selector:
    matchLabels:
      app: ingress-nginx
  template:
    metadata:
      labels:
        app: ingress-nginx
      annotations:
        prometheus.io/port: '10254'
        prometheus.io/scrape: 'true'
        # Do not redirect inbound traffic to Envoy.
        traffic.sidecar.istio.io/includeInboundPorts: ""
        traffic.sidecar.istio.io/excludeInboundPorts: "80,443"
        # Exclude outbound traffic to kubernetes master from redirection.
        traffic.sidecar.istio.io/excludeOutboundIPRanges: __KUBE_API_SERVER_IP__
        sidecar.istio.io/inject: 'true'
    spec:
      serviceAccountName: nginx-ingress-serviceaccount
      containers:
        - name: nginx
          image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.12.0
          securityContext:
            runAsUser: 0
          args:
            - /nginx-ingress-controller
            - --default-backend-service=$(POD_NAMESPACE)/nginx-default-http-backend
            - --configmap=$(POD_NAMESPACE)/nginx-configuration
            - --tcp-services-configmap=$(POD_NAMESPACE)/nginx-tcp-services
            - --udp-services-configmap=$(POD_NAMESPACE)/nginx-udp-services
            - --annotations-prefix=nginx.ingress.kubernetes.io
            - --v=10
          env:
            - name: POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
            - name: POD_NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
          ports:
          - name: http
            containerPort: 80
          - name: https
            containerPort: 443
          livenessProbe:
            failureThreshold: 8
            initialDelaySeconds: 15
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 1
            httpGet:
              path: /healthz
              port: 10254
              scheme: HTTP
          readinessProbe:
            failureThreshold: 8
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 1
            httpGet:
              path: /healthz
              port: 10254
              scheme: HTTP
---
# Service: ingress-nginx
apiVersion: v1
kind: Service
metadata:
  name: ingress-nginx
  namespace: default
  labels:
    app: ingress-nginx
spec:
  type: LoadBalancer
  selector:
    app: ingress-nginx
  ports:
  - name: http
    port: 80
    targetPort: http
  - name: https
    port: 443
    targetPort: https
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-configuration
  namespace: default
  labels:
    app: ingress-nginx
data:
  ssl-redirect: "false"
---

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-tcp-services
  namespace: default
  labels:
    app: ingress-nginx
---

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-udp-services
  namespace: default
  labels:
    app: ingress-nginx
---

apiVersion: v1
kind: ServiceAccount
metadata:
  name: nginx-ingress-serviceaccount
  namespace: default

---

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
  name: nginx-ingress-clusterrole
  namespace: default
rules:
  - apiGroups:
      - ""
    resources:
      - configmaps
      - endpoints
      - nodes
      - pods
      - secrets
    verbs:
      - list
      - watch
  - apiGroups:
      - ""
    resources:
      - nodes
    verbs:
      - get
  - apiGroups:
      - ""
    resources:
      - services
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - "extensions"
    resources:
      - ingresses
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - ""
    resources:
        - events
    verbs:
        - create
        - patch
  - apiGroups:
      - "extensions"
    resources:
      - ingresses/status
    verbs:
      - update

---

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: Role
metadata:
  name: nginx-ingress-role
  namespace: default
rules:
  - apiGroups:
      - ""
    resources:
      - configmaps
      - pods
      - secrets
      - namespaces
    verbs:
      - get
  - apiGroups:
      - ""
    resources:
      - configmaps
    resourceNames:
      # Defaults to "<election-id>-<ingress-class>"
      # Here: "<ingress-controller-leader>-<nginx>"
      # This has to be adapted if you change either parameter
      # when launching the nginx-ingress-controller.
      - "ingress-controller-leader-nginx"
    verbs:
      - get
      - update
  - apiGroups:
      - ""
    resources:
      - configmaps
    verbs:
      - create
  - apiGroups:
      - ""
    resources:
      - endpoints
    verbs:
      - get

---

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: RoleBinding
metadata:
  name: nginx-ingress-role-nisa-binding
  namespace: default
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: nginx-ingress-role
subjects:
  - kind: ServiceAccount
    name: nginx-ingress-serviceaccount

---

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: nginx-ingress-clusterrole-nisa-binding
  namespace: default
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: nginx-ingress-clusterrole
subjects:
  - kind: ServiceAccount
    name: nginx-ingress-serviceaccount
    namespace: default
---

# Deployment: nginx-default-http-backend
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-default-http-backend
  namespace: default
  labels:
    app: nginx-default-http-backend
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx-default-http-backend
  template:
    metadata:
      labels:
        app: nginx-default-http-backend
        # rewrite kubelet's probe request to pilot agent to prevent health check failure under mtls
        annotations: sidecar.istio.io/rewriteAppHTTPProbers: "true"
    spec:
      terminationGracePeriodSeconds: 60
      containers:
      - name: backend
        # Any image is permissible as long as:
        # 1. It serves a 404 page at /
        # 2. It serves 200 on a /healthz endpoint
        image: gcr.io/google_containers/defaultbackend:1.4
        securityContext:
          runAsUser: 0
        ports:
        - name: http
          containerPort: 8080
        livenessProbe:
          httpGet:
            path: /healthz
            port: 8080
            scheme: HTTP
          initialDelaySeconds: 30
          timeoutSeconds: 5
        resources:
          limits:
            cpu: 10m
            memory: 20Mi
          requests:
            cpu: 10m
            memory: 20Mi
---

# Service: nginx-default-http-backend
apiVersion: v1
kind: Service
metadata:
  name: nginx-default-http-backend
  namespace: default
  labels:
    app: nginx-default-http-backend
spec:
  ports:
  - name: http
    port: 80
    targetPort: http
  selector:
    app: nginx-default-http-backend
---

Deploy NGINX ingress controller and config into ingress namespace:

kubectl create namespace ingress
kubectl label namespace ingress istio-injection=enabled
sed "s#__KUBE_API_SERVER_IP__#${KUBE_API_SERVER_IP}#" nginx-ingress-ns.yaml | kubectl apply -n ingress -f -

Ingress configuration file:

\# nginx-ingress-ns.yaml
# Deployment: nginx-ingress-controller
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-ingress-controller
  namespace: ingress
spec:
  replicas: 1
  selector:
    matchLabels:
      app: ingress-nginx
  template:
    metadata:
      labels:
        app: ingress-nginx
      annotations:
        prometheus.io/port: '10254'
        prometheus.io/scrape: 'true'
        # Do not redirect inbound traffic to Envoy.
        traffic.sidecar.istio.io/includeInboundPorts: ""
        traffic.sidecar.istio.io/excludeInboundPorts: "80,443"
        # Exclude outbound traffic to kubernetes master from redirection.
        traffic.sidecar.istio.io/excludeOutboundIPRanges: __KUBE_API_SERVER_IP__
        sidecar.istio.io/inject: 'true'
    spec:
      serviceAccountName: nginx-ingress-serviceaccount
      containers:
        - name: nginx
          image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.12.0
          securityContext:
            runAsUser: 0
          args:
            - /nginx-ingress-controller
            - --default-backend-service=$(POD_NAMESPACE)/nginx-default-http-backend
            - --configmap=$(POD_NAMESPACE)/nginx-configuration
            - --tcp-services-configmap=$(POD_NAMESPACE)/nginx-tcp-services
            - --udp-services-configmap=$(POD_NAMESPACE)/nginx-udp-services
            - --annotations-prefix=nginx.ingress.kubernetes.io
            - --v=10
          env:
            - name: POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
            - name: POD_NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
          ports:
          - name: http
            containerPort: 80
          - name: https
            containerPort: 443
          livenessProbe:
            failureThreshold: 8
            initialDelaySeconds: 15
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 1
            httpGet:
              path: /healthz
              port: 10254
              scheme: HTTP
          readinessProbe:
            failureThreshold: 8
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 1
            httpGet:
              path: /healthz
              port: 10254
              scheme: HTTP
---
# Service: ingress-nginx
apiVersion: v1
kind: Service
metadata:
  name: ingress-nginx
  namespace: ingress
  labels:
    app: ingress-nginx
spec:
  type: LoadBalancer
  selector:
    app: ingress-nginx
  ports:
  - name: http
    port: 80
    targetPort: http
  - name: https
    port: 443
    targetPort: https
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-configuration
  namespace: ingress
  labels:
    app: ingress-nginx
data:
  ssl-redirect: "false"
---

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-tcp-services
  namespace: ingress
  labels:
    app: ingress-nginx
---

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-udp-services
  namespace: ingress
  labels:
    app: ingress-nginx
---

apiVersion: v1
kind: ServiceAccount
metadata:
  name: nginx-ingress-serviceaccount
  namespace: ingress

---

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
  name: nginx-ingress-clusterrole
  namespace: ingress
rules:
  - apiGroups:
      - ""
    resources:
      - configmaps
      - endpoints
      - nodes
      - pods
      - secrets
    verbs:
      - list
      - watch
  - apiGroups:
      - ""
    resources:
      - nodes
    verbs:
      - get
  - apiGroups:
      - ""
    resources:
      - services
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - "extensions"
    resources:
      - ingresses
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - ""
    resources:
        - events
    verbs:
        - create
        - patch
  - apiGroups:
      - "extensions"
    resources:
      - ingresses/status
    verbs:
      - update

---

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: Role
metadata:
  name: nginx-ingress-role
  namespace: ingress
rules:
  - apiGroups:
      - ""
    resources:
      - configmaps
      - pods
      - secrets
      - namespaces
    verbs:
      - get
  - apiGroups:
      - ""
    resources:
      - configmaps
    resourceNames:
      # Defaults to "<election-id>-<ingress-class>"
      # Here: "<ingress-controller-leader>-<nginx>"
      # This has to be adapted if you change either parameter
      # when launching the nginx-ingress-controller.
      - "ingress-controller-leader-nginx"
    verbs:
      - get
      - update
  - apiGroups:
      - ""
    resources:
      - configmaps
    verbs:
      - create
  - apiGroups:
      - ""
    resources:
      - endpoints
    verbs:
      - get

---

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: RoleBinding
metadata:
  name: nginx-ingress-role-nisa-binding
  namespace: ingress
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: nginx-ingress-role
subjects:
  - kind: ServiceAccount
    name: nginx-ingress-serviceaccount

---

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: nginx-ingress-clusterrole-nisa-binding
  namespace: ingress
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: nginx-ingress-clusterrole
subjects:
  - kind: ServiceAccount
    name: nginx-ingress-serviceaccount
    namespace: ingress
---

# Deployment: nginx-default-http-backend
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-default-http-backend
  namespace: ingress
  labels:
    app: nginx-default-http-backend
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx-default-http-backend
  template:
    metadata:
      labels:
        app: nginx-default-http-backend
      # rewrite kubelet's probe request to pilot agent to prevent health check failure under mtls
      annotations:
        sidecar.istio.io/rewriteAppHTTPProbers: "true"
    spec:
      terminationGracePeriodSeconds: 60
      containers:
      - name: backend
        # Any image is permissible as long as:
        # 1. It serves a 404 page at /
        # 2. It serves 200 on a /healthz endpoint
        image: gcr.io/google_containers/defaultbackend:1.4
        securityContext:
          runAsUser: 0
        ports:
        - name: http
          containerPort: 8080
        livenessProbe:
          httpGet:
            path: /healthz
            port: 8080
            scheme: HTTP
          initialDelaySeconds: 30
          timeoutSeconds: 5
        resources:
          limits:
            cpu: 10m
            memory: 20Mi
          requests:
            cpu: 10m
            memory: 20Mi
---

# Service: nginx-default-http-backend
apiVersion: v1
kind: Service
metadata:
  name: nginx-default-http-backend
  namespace: ingress
  labels:
    app: nginx-default-http-backend
spec:
  ports:
  - name: http
    port: 80
    targetPort: http
  selector:
    app: nginx-default-http-backend
---

Create the Ingress resource routing to httpbin:

kubectl apply -f ingress-ingress-ns.yaml

\# ingress-ingress-ns.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: nginx-ingress
namespace: ingress
annotations:
kubernetes.io/ingress.class: nginx
nginx.ingress.kubernetes.io/service-upstream: "true"
nginx.ingress.kubernetes.io/upstream-vhost: httpbin.default.svc.cluster.local

spec:
backend:
serviceName: httpbin
servicePort: 8000

Create the sidecar resource that allows traffic from the ingress namespace to default:

kubectl apply -f sidecar-ingress-ns.yaml

\# sidecar-ingress-ns.yaml
apiVersion: networking.istio.io/v1alpha3
kind: Sidecar
metadata:
name: ingress
namespace: ingress
spec:
egress:
- hosts:
- "default/\*"
# tripping hazard: make sure you include istio-system!
- "istio-system/\*"

Verify that external traffic can be routed to the httpbin service via nginx ingress in both default and ingress namespaces:a. Verify traffic into the nginx ingress from the default namespace:

curl $(kubectl get svc -n default ingress-nginx -o jsonpath='{.status.loadBalancer.ingress[0].ip}')/ip -v

b. Verify traffic into the nginx ingress from the ingress namespace:

curl $(kubectl get svc -n ingress ingress-nginx -o
  jsonpath='{.status.loadBalancer.ingress[0].ip}')/ip

c. Expected response for both requests should look something like this:

\* Trying 34.83.167.92...
  \* TCP_NODELAY set
  \* Connected to 34.83.167.92 (34.83.167.92) port 80 (#0)
  > GET /ip HTTP/1.1
  > Host: 34.83.167.92
  > User-Agent: curl/7.58.0
  > Accept: \*/\*
  >
  < HTTP/1.1 200 OK
  < Server: nginx/1.13.9
  < Date: Mon, 17 Feb 2020 21:06:18 GMT
  < Content-Type: application/json
  < Content-Length: 30
  < Connection: keep-alive
  < access-control-allow-origin: \*
  < access-control-allow-credentials: true
  < x-envoy-upstream-service-time: 2
  <
  {
    "origin": "10.138.0.13"
  }
  \* Connection #0 to host 34.83.167.92 left intact

Verify that the httpbin service does not receive traffic in plaintext:a. Execute the following in shell

kubectl create namespace legacy
  kubectl apply -f ./istio-1.4.2/samples/sleep/sleep.yaml -n legacy
  kubectl exec -it $(kubectl get pod -n legacy -l app=sleep -o
  jsonpath='{.items[0].metadata.name}') -n legacy -- curl
  httpbin.default.svc.cluster.local:8000/ip -v

b. The following output is expected

\* Expire in 0 ms for 6 (transfer 0x55d92c811680)
  \* Expire in 15 ms for 1 (transfer 0x55dc9cca6680)
  \*   Trying 10.15.247.45...
  \* TCP_NODELAY set
  \* Expire in 200 ms for 4 (transfer 0x55dc9cca6680)
  \* Connected to httpbin.default.svc.cluster.local (10.15.247.45) port 8000 (#0)
  > GET /ip HTTP/1.1
  > Host: httpbin.default.svc.cluster.local:8000
  > User-Agent: curl/7.64.0
  > Accept: \*/\*
  >
  \* Recv failure: Connection reset by peer
  \* Closing connection 0
  curl: (56) Recv failure: Connection reset by peer
  command terminated with exit code 56

Verify that the connection between nginx-ingress-controller and httpbin service are mtls enableda. Use istioctl cli to verify the authentication policy

./istio-1.4.2/bin/istioctl authn tls-check $(kubectl get pod -n default -l app=ingress-nginx -o jsonpath='{.items[0].metadata.name}') httpbin.default.svc.cluster.local
./istio-1.4.2/bin/istioctl authn tls-check -n ingress $(kubectl get pod -n ingress -l app=ingress-nginx -o jsonpath='{.items[0].metadata.name}') httpbin.default.svc.cluster.local

b. Expected output log for both nginx ingress

HOST:PORT                                              STATUS     SERVER     CLIENT           AUTHN POLICY     DESTINATION RULE
httpbin.default.svc.cluster.local:8000     OK         STRICT     ISTIO_MUTUAL     /default         istio-system/default