流量转移

本任务将向您展示如何在 Kmesh 中为 HTTP 流量设置流量转移策略。

开始之前

• 安装 Kmesh

  请参考快速入门并切换到内核原生模式(Kernel Native Mode)。

• 部署 Fortio 应用程序

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

• 检查应用程序状态并确保服务应用程序由 Kmesh 管理

  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

测试路由配置

• 使用以下命令显示已定义的路由：

  $ 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: ""

• 您已配置 Fortio 将 90% 的流量路由到 Fortio 服务器的 v1 版本

  $ 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

基于用户身份的路由

• 接下来，您将更改路由配置，以便来自特定用户的所有流量都路由到特定的服务版本。在这种情况下，来自名为 Jason 的用户的所有流量都将路由到服务 fortio:v2。

• 应用更新后的配置：

  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

• 验证来自 Server 1 的响应：

  $ 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

了解发生了什么

在本任务中，您使用 Kmesh 的加权路由功能将流量从 fortio 服务的旧版本迁移到新版本。

使用 Kmesh，您可以让 fortio 服务的两个版本独立地扩展和缩减，而不影响它们之间的流量分配。

清理

1. 删除应用程序路由规则：

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

2. 删除 Kmesh：

   • 请参考清理。