Traffic Shifting

This task shows you how to set up Traffic Shifting policy for http traffic in Kmesh.

Before you begin

Install Kmesh

Please refer quickstart and change into ads mode
Deploy the fortio Applications

kubectl apply -f samples/fortio/fortio-route.yaml
kubectl apply -f samples/fortio/netutils.yaml

Check app status and ensure that the service application is managed by Kmesh

kubectl get pod 
NAME                         READY   STATUS    RESTARTS   AGE
fortio-v1-596b55cb8b-sfktr   1/1     Running   0          57m
fortio-v2-76997f99f4-qjsmd   1/1     Running   0          57m
netutils-575f5c569-lr98z     1/1     Running   0          67m

kubectl describe pod netutils-575f5c569-lr98z | grep Annotations
Annotations:      kmesh.net/redirection: enabled

Test the routing configuration

Display the defined routes with the following command:

$ kubectl get virtualservices -o yaml
apiVersion: v1
items:
- apiVersion: networking.istio.io/v1beta1
  kind: VirtualService
  metadata:
    annotations:
      kubectl.kubernetes.io/last-applied-configuration: |
        {"apiVersion":"networking.istio.io/v1alpha3","kind":"VirtualService","metadata":{"annotations":{},"name":"fortio","namespace":"default"},"spec":{"hosts":["fortio"],"http":[{"route":[{"destination":{"host":"fortio","subset":"v1"},"weight":90},{"destination":{"host":"fortio","subset":"v2"},"weight":10}]}]}}
    creationTimestamp: "2024-07-09T09:00:36Z"
    generation: 1
    name: fortio
    namespace: default
    resourceVersion: "11166"
    uid: 0a07f283-ac26-4d86-b3bd-ce6aa07dc628
  spec:
    hosts:
    - fortio
    http:
    - route:
      - destination:
          host: fortio
          subset: v1
        weight: 90
      - destination:
          host: fortio
          subset: v2
        weight: 10
kind: List
metadata:
  resourceVersion: ""

You have configured fortio 90% to route to the v1 version of the fortio server

$ for i in {1..20}; do kubectl exec -it $(kubectl get pod | grep netutils | awk '{print $1}') -- curl -v $(kubectl get svc -owide | grep fortio | awk '{print $3}'):80 | grep "Server:"; done
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 2
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 1
< Server: 2
< Server: 1
< Server: 1

Route based on user identity

Next, you will change the route configuration so that all traffic from a specific user is routed to a specific service version. In this case, all traffic from a user named Jason will be routed to the service fortio:v2.

kubectl apply -f samples/fortio/fortio-v1-10-v2-90.yaml

fortio-header.yaml

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: fortio
spec:
  hosts:
  - fortio
  http:
  - route:
    - destination:
        host: fortio
        subset: v1
      weight: 10
    - destination:
        host: fortio
        subset: v2
      weight: 90

Verify response from Server 1

$ for i in {1..20}; do kubectl exec -it $(kubectl get pod | grep netutils | awk '{print $1}') -- curl -v $(kubectl get svc -owide | grep fortio | awk '{print $3}'):80 | grep "Server:"; done
< Server: 2
< Server: 2
< Server: 1
< Server: 2
< Server: 1
< Server: 2
< Server: 2
< Server: 2
< Server: 2
< Server: 2
< Server: 2
< Server: 2
< Server: 1
< Server: 2
< Server: 2
< Server: 2
< Server: 1
< Server: 2
< Server: 2
< Server: 2

Understanding what happened

In this task you migrated traffic from an old to new version of the fortio service using kmesh’s weighted routing feature.

With Kmesh, you can allow the two versions of the fortio service to scale up and down independently, without affecting the traffic distribution between them.

Clean up

Remove the application route rules

kubectl delete -f samples/fortio/fortio-route.yaml
kubectl delete -f samples/fortio/netutils.yaml

Remove kmesh

Please refer cleanup

Last updated on Sep 10, 2024