Configure mirroring - Alibaba Cloud Service Mesh - Alibaba Cloud Documentation Center

You can use Service Mesh (ASM) to send a copy of traffic destined for a service to a mirrored service. This topic describes how to configure mirroring.

Prerequisites

The preparations are completed, and the mocka and sleep services are deployed. For more information, see Preparations.

Procedure

Check whether the service configurations take effect.
1. Use kubectl to connect to the Container Service for Kubernetes (ACK) cluster based on the information in the kubeconfig file, and then run the following command to enable bash for the sleep service:
```
kubectl exec -it deploy/sleep -- sh
```
2. Run the following command to send a request to the mocka service:
```
curl mocka:8000/mock
```
  The expected output is that mocka-v1 or mocka-v2 randomly responds to the request.
```
-> mocka(version: v1, ip: 192.168.1.246)
-> mocka(version: v2, ip: 192.168.1.53)
```
Use the istioctl tool to run the following command to deploy a Layer 7 waypoint proxy for the mocka service:
```
istioctl x waypoint apply --service-account mocka
```

Configure a traffic rule for the mocka service, configure mocka-v1 to receive and respond to requests, and mirror the requests to mocka-v2.

Use the following content to create a destination rule. For more information, see Manage destination rules.

apiVersion: networking.istio.io/v1beta1
kind: DestinationRule
metadata:
  name: mocka
  namespace: default
spec:
  host: mocka
  subsets:
    - labels:
        version: v1
      name: v1
    - labels:
        version: v2
      name: v2

Use the following content to create a virtual service. For more information, see Manage virtual services.

apiVersion: networking.istio.io/v1beta1
kind: VirtualService
metadata:
  name: mocka
  namespace: default
spec:
  hosts:
    - mocka
  http:
    - match:
        - uri:
            exact: /mock
      mirror:
        host: mocka
        subset: v2
      route:
        - destination:
            host: mocka
            subset: v1

Check whether the configurations take effect.

Use kubectl to connect to the ACK cluster based on the information in the kubeconfig file, and then run the following command to enable bash for the sleep service:
```
kubectl exec -it deploy/sleep -- sh
```
Run the following command to send a request to the mocka service:
```
curl mocka:8000/mock
```
The expected output is always that mocka-v1 responds to the request.
```
-> mocka(version: v1, ip: 192.168.1.246)
```

Run the following commands to view the logs of mocka-v2:

# View the name of the mocka-v2 Pod: 
kubectl get pods 
# View the logs of the mocka-v2 pod: 
kubectl logs {Name of the mocka-v2 pod}

Expected output:

receive request: x-request-id: 6f11e7b9-dc6c-4e57-aa52-c2644f8d****
receive request: x-request-id: e9cedc48-d5c1-4233-a97b-5cb88f0d****
receive request: x-request-id: bf4e4bb2-7339-42a0-a70f-eab7905d****
receive request: x-request-id: 4779fb9a-f9c5-47c2-b9f7-8dc097cd****
receive request: x-request-id: f32f012a-669d-48a4-a992-473068dd****
receive request: x-request-id: 3ef4a1e7-4301-45db-ad1c-6b35bd1d****
...

The output indicates that mocka-v2 also receives the requests. If requests are continuously sent to mocka-v1, the logs of mocka-v2 indicate that mocka-v2 receives requests continuously.