kubernetes集群编排——istio

官网：https://istio.io/latest/zh/about/service-mesh/

部署

[root@k8s2 ~]# tar zxf istio-1.19.3-linux-amd64.tar.gz

[root@k8s2 ~]# cd istio-1.19.3/
 
[root@k8s2 istio-1.19.3]# export PATH=$PWD/bin:$PATH

demo专为测试准备的功能集合

[root@k8s2 istio-1.19.3]# istioctl install --set profile=demo -y

[root@k8s2 istio-1.19.3]# kubectl get pod -A

给命名空间添加标签，指示 Istio 在部署应用的时候，自动注入 Envoy 边车代理

[root@k8s2 istio-1.19.3]# kubectl label namespace default istio-injection=enabled

部署示例应用

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/platform/kube/bookinfo.yaml

[root@k8s2 istio-1.19.3]# kubectl get pod

创建 Istio 入站网关

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/networking/bookinfo-gateway.yaml

[root@k8s2 istio-1.19.3]# kubectl -n istio-system get svc

访问应用：http://192.168.92.102/productpage

部署遥测组件

[root@k8s2 istio-1.17.1]# kubectl apply -f samples/addons

待插件部署完毕后，修改kiali服务的访问方式为Loadbalancer

访问kiali：http://192.168.56.100:20001/

流量管理

将所有流量路由到每个微服务的 v1 版本

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/networking/destination-rule-all.yaml
 
[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/networking/virtual-service-all-v1.yaml

来自名为 Jason 的用户的所有流量将被路由到服务 reviews:v2

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/networking/virtual-service-reviews-test-v2.yaml

创建故障注入规则以延迟来自测试用户 jason 的流量

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/networking/virtual-service-ratings-test-delay.yaml

用户 jason 登陆到 /productpage 页面,出现了一个问题：Reviews 部分显示了错误消息

设置流量转移，将所有流量转移到 reviews:v3

[root@k8s2 istio-1.19.3]# vim  samples/bookinfo/networking/virtual-service-reviews-test-v2.yaml

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: reviews
spec:
  hosts:
    - reviews
  http:
  - match:
    - headers:
        end-user:
          exact: jason
    route:
    - destination:
        host: reviews
        subset: v3
  - route:
    - destination:
        host: reviews
        subset: v1

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/networking/virtual-service-reviews-test-v2.yaml

修改延迟规则为任何低于 2.5 秒的数值，例如 2 秒

[root@k8s2 istio-1.19.3]# vim  samples/bookinfo/networking/virtual-service-ratings-test-delay.yaml

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: ratings
spec:
  hosts:
  - ratings
  http:
  - match:
    - headers:
        end-user:
          exact: jason
    fault:
      delay:
        percentage:
          value: 100.0
        fixedDelay: 2s
    route:
    - destination:
        host: ratings
        subset: v1
  - route:
    - destination:
        host: ratings
        subset: v1

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/networking/virtual-service-ratings-test-delay.yaml

把 50% 的流量从 reviews:v1 转移到 reviews:v3

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/networking/virtual-service-reviews-50-v3.yaml

当reviews:v3 微服务已经稳定，可以通过应用 Virtual Service 规则将 100% 的流量路由 reviews:v3：

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/bookinfo/networking/virtual-service-reviews-v3.yaml

清理

[root@k8s2 istio-1.19.3]# samples/bookinfo/platform/kube/cleanup.sh

熔断

部署 httpbin 服务

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/httpbin/httpbin.yaml

配置熔断规则

[root@k8s2 istio-1.19.3]# kubectl apply -f - <<EOF
> apiVersion: networking.istio.io/v1alpha3
> kind: DestinationRule
> metadata:
>   name: httpbin
> spec:
>   host: httpbin
>   trafficPolicy:
>     connectionPool:
>       tcp:
>         maxConnections: 1
>       http:
>         http1MaxPendingRequests: 1
>         maxRequestsPerConnection: 1
>     outlierDetection:
>       consecutive5xxErrors: 1
>       interval: 1s
>       baseEjectionTime: 3m
>       maxEjectionPercent: 100
> EOF

增加一个客户端

[root@k8s2 istio-1.19.3]# kubectl apply -f samples/httpbin/sample-client/fortio-deploy.yaml

[root@k8s2 istio-1.19.3]# kubectl get pod
 
[root@k8s2 istio-1.19.3]# kubectl get svc

登入客户端 Pod 并使用 Fortio 工具调用 httpbin 服务

[root@k8s2 istio-1.19.3]# export FORTIO_POD=$(kubectl get pods -l app=fortio -o 'jsonpath={.items[0].metadata.name}')
 
 
[root@k8s2 istio-1.19.3]# kubectl exec "$FORTIO_POD" -c fortio -- /usr/bin/fortio curl -quiet http://httpbin:8000/get

触发熔断器

发送并发数为 2 的连接（-c 2），请求 20 次（-n 20）

[root@k8s2 istio-1.19.3]# kubectl exec "$FORTIO_POD" -c fortio -- /usr/bin/fortio load -c 2 -qps 0 -n 20 -loglevel Warning http://httpbin:8000/get

istio-proxy 确实允许存在一些误差

将并发连接数提高到 3 个

[root@k8s2 istio-1.19.3]# kubectl exec "$FORTIO_POD" -c fortio -- /usr/bin/fortio load -c 3 -qps 0 -n 30 -loglevel Warning http://httpbin:8000/get

将并发连接数提高到 5 个

[root@k8s2 istio-1.19.3]# kubectl exec "$FORTIO_POD" -c fortio -- /usr/bin/fortio load -c 5 -qps 0 -n 30 -loglevel Warning http://httpbin:8000/get

均被熔断器拦截

清理

[root@k8s2 istio-1.19.3]# kubectl delete destinationrule httpbin
 
[root@k8s2 istio-1.19.3]# kubectl delete -f samples/httpbin/sample-client/fortio-deploy.yaml
 
[root@k8s2 istio-1.19.3]# kubectl delete -f samples/httpbin/httpbin.yaml

卸载istio

[root@k8s2 istio-1.19.3]# istioctl uninstall -y --purge

[root@k8s2 istio-1.19.3]# kubectl label namespace default istio-injection-