Kmesh v0.2.0 needs to be restarted for configuration changes to take effect (using Istio 1.19 and Kubernetes 1.27)

[tmodak27]

What happened:

With Kmesh v0.2.0 already running, I deployed a Virtual Service for L7 url routing. Below are my two observations

1. The exported bpf config was NOT updated with the routing rule
2. The request did NOT get routed as expected.

However, after restarting Kmesh, the following was observed

1. The exported bpf config was updated with the routing rule
2. The request got routed as expected.

For reference, refer to this comment from another github issue:

#133 (comment)
#133 (comment)

What you expected to happen:

After deploying the virtual service, the bpf map should get updated and the routing should take effect WITHOUT having to restart Kmesh

How to reproduce it (as minimally and precisely as possible):

Run the below steps with Kmesh v0.2.0 already running

Step 1

Deploy 2 Backend Services httpecho-a and httpecho-b

• yaml for service httpecho-a

# kubectl  apply -f service-a.yaml
apiVersion: v1
kind: Service
metadata:
  name: httpecho-a
  labels:
    app: httpecho-a
    service: httpecho-a
spec:
  ports:
  - port: 5000
    name: http
  selector:
    app: httpecho-a
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: httpecho-a
  labels:
    app: httpecho-a
    version: v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: httpecho-a
      version: v1
  template:
    metadata:
      labels:
        app: httpecho-a
        version: v1
    spec:
      containers:
      - name: httpecho-a
        image: docker.io/istio/examples-helloworld-v1
        resources:
          requests:
            cpu: "100m"
        imagePullPolicy: IfNotPresent #Always
        ports:
        - containerPort: 5000

• yaml for httpecho-b

# kubectly apply -f service-b.yaml
apiVersion: v1
kind: Service
metadata:
  name: httpecho-b
  labels:
    app: httpecho-b
    service: httpecho-b
spec:
  ports:
  - port: 5000
    name: httpb
  selector:
    app: httpecho-b
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: httpecho-b
  labels:
    app: httpecho-b
    version: v2
spec:
  replicas: 1
  selector:
    matchLabels:
      app: httpecho-b
      version: v2
  template:
    metadata:
      labels:
        app: httpecho-b
        version: v2
    spec:
      containers:
      - name: httpecho-b
        image: docker.io/istio/examples-helloworld-v1
        resources:
          requests:
            cpu: "100m"
        imagePullPolicy: IfNotPresent #Always
        ports:
        - containerPort: 5000

Step 2: Deploy netutils client for sending http requests

kubectl run --image=hwchiu/netutils netutils

Send requests to http-echo-a and httpecho-b with the netutils client. Note the difference in pod names in the response from each service

$ kubectl exec -it netutils -- curl httpecho-a:5000
Hello V1, routed from pod httpecho-a-gu83s


$ kubectl exec -it netutils -- curl httpecho-b:5000
Hello V1, routed from pod httpecho-b-t7wx5

Step 3: Deploy Virtual Service for L7 Url Routing

This rule should route all requests sent to httpecho-b to httpecho-a instead

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: route-b-to-a
spec:
  hosts:
  - httpecho-b
  http:
  - match:
    - port: 5000
    route:
    - destination:
        host: httpecho-a.default.svc.cluster.local
        port:
          number: 5000

Step 4: Send request to httpecho-b

Note the pod name in the response. If routing works, it should be httpecho-a-gu83s, and NOT httpecho-b-t7wx5.

$ kubectl exec -it netutils -- curl  httpecho-b:5000/hello
Hello V1, routed from pod httpecho-b-t7wx5

Also, export the bpf config using curl GET /bpf/kmesh/maps:15200. The newly added rule is NOT a part of the bpf config.

Step 4: Restart Kmesh and run the above command once again:

The request gets routed to httpecho-a

$ kubectl exec -it netutils -- curl  httpecho-b:5000/hello
Hello V1, routed from pod httpecho-a-gu83s

export the bpf config using curl GET /bpf/kmesh/maps:15200. The newly added rule is a part of the exported bpf config.

The same issue occurs when we try to delete the routing rule. The request keeps getting routed to httpecho-a. Once we restart kmesh, the request gets routed to httpecho-b

Anything else we need to know?:

Environment:

• Kmesh version: v0.2.0
• Istio: 1.19.0
• Kubernetes: 1.27.0

[nlgwcy]

cc @lec-bit

[supercharge-xsy]

A code optimization is required：The resource name field needs to be filled in newAckRequest when the xDS type is RDS or EDS， will fix it @lec-bit