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kubernetesistio

Istio Send Request to wrong subset pod

I try to do a mirror test of my service

But I haven't configured the mirror testing config yet, but Pod b has already received the traffic. It seems that the Service distributes the traffic instead of being controlled by VirtualService ?

Or do I have a setting error there?

Here I create a sample about it

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: helloworld
spec:
  hosts:
    - helloworld
  http:
  - route:
    - destination:
        host: helloworld
        subset: v1
      weight: 100
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
  name: helloworld
spec:
  host: helloworld
  subsets:
  - name: v1
    labels:
      version: v1
---
apiVersion: v1
kind: Service
metadata:
  name: helloworld
  labels:
    app: helloworld
    service: helloworld
spec:
  selector:
    app: helloworld
  ports:
  - name: http
    protocol: TCP
    port: 80
    targetPort: 3000
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: helloworld-v1
  labels:
    app: helloworld
    version: v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: helloworld
      version: v1
  template:
    metadata:
      labels:
        app: helloworld
        version: v1
    spec:
      containers:
        - name: helloworld-v1
          image: surprised128/nodetestserver:log
          ports:
            - containerPort: 3000
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: helloworld-v2
  labels:
    app: helloworld
    version: v2
spec:
  replicas: 1
  selector:
    matchLabels:
      app: helloworld
      version: v2
  template:
    metadata:
      labels:
        app: helloworld
        version: v2
    spec:
      containers:
        - name: helloworld-v2
          image: surprised128/nodetestserver:v2
          ports:
            - containerPort: 3000

And I use curl to send request, then we can see the response was contain result of v1 and v2.

for i in `seq 1 100`; do curl http://helloworld.connext3.svc.cluster.local/nodejs/hello; done

enter image description here Here is the istioctl test, nothing looks wrong enter image description here

This Yaml is work well in istio version 1.13.0, but fail in 1.16.4, Are there any differences between versions?

Solution

  • Finally, I found the problem. The root cause was the pod which I using to curl target service was out of istio service mesh(means it has no istio proxy sidecar in pod)

    So the request from this pod was pass by k8s service, not managed by the virtual service or destination rule.

    https://istio.io/latest/docs/ops/deployment/requirements/

    In order to support Istio’s traffic routing capabilities, traffic leaving a pod may be routed differently than when a sidecar is not deployed.