Service 引入主要是解决方案 Pod 的动态变化，提供统一访问入口：
- 防止 Pod 失去联系，准备找到提供的服务 Pod (服务发现)
- 定义一组 Pod 的访问策略 (负载均衡)
部署 deploy
kubectl apply -f deploy.yamlapiVersion: apps/v1 kind: Deployment metadata: name: chiyi-nginx spec: replicas: 3 selector: matchLabels: app: chiyi-nginx template: metadata: labels: app: chiyi-nginx spec: containers: - name: nginx image: nginx:1.14.2 ports: - containerPort: 80部署 service
kubectl apply -f service.yamlapiVersion: v1 kind: Service metadata: name: chiyi-nginx spec: selector: app: chiyi-nginx ports: - protocol: TCP port: 80 targetPort: 80 nodePort: 30002 type: NodePort查看 service 和 pod 的关系
kubectl get ep curl 10.244.1.58:80说明：
Service 一组通过标签关联 Pod
Service 为一组 Pod 提供负载平衡能力
[root@k8s-master service]# kubectl get ep NAME ENDPOINTS AGE chiyi-nginx 10.244.1.58:80,10.244.1.59:80,10.244.2.46:80 5m19s kubernetes 172.17.28.225:6443 23h [root@k8s-master service]# curl 10.244.1.58:80 <!DOCTYPE html> <html> <head> <title>Welcome to nginx!</title> <style> body { width: 35em; margin: 0 auto; font-family: Tahoma, Verdana, Arial, sans-serif; } </style> </head> <body> <h1>Welcome to nginx!</h1> <p>If you see this page, the nginx web server is successfully installed and working. Further configuration is required.</p> <p>For online documentation and support please refer to <a href="http://nginx.org/">nginx.org</a>.<br/> Commercial support is available at <a href="http://nginx.com/">nginx.com</a>.</p> <p><em>Thank you for using nginx.</em></p> </body> </html> 查看 service
kubectl get service curl 10.101.104.218[root@k8s-master service]# kubectl get service NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE chiyi-nginx NodePort 10.101.104.218 <none> 80:30002/TCP 6m3s kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 23h [root@k8s-master service]# curl 10.101.104.218 <!DOCTYPE html> <html> <head> <title>Welcome to nginx!</title> <style> body { width: 35em; margin: 0 auto; font-family: Tahoma, Verdana, Arial, sans-serif; } </style> </head> <body> <h1>Welcome to nginx!</h1> <p>If you see this page, the nginx web server is successfully installed and working. Further configuration is required.</p> <p>For online documentation and support please refer to <a href="http://nginx.org/">nginx.org</a>.<br/> Commercial support is available at <a href="http://nginx.com/">nginx.com</a>.</p> <p><em>Thank you for using nginx.</em></p> </body> </html> 查看端口
ss -antp |grep 30002[root@k8s-master service]# ss -antp |grep 30002 LISTEN 0 128 *:30002 *:* users:(("kube-proxy",pid=3544,fd=13))导出 yaml
kubectl get service chiyi-nginx -o yaml筛选 service 关联 pod
kubectl get pods -l app=chiyi-nginx[root@k8s-master service]# kubectl get pods -l app=chiyi-nginx NAME READY STATUS RESTARTS AGE chiyi-nginx-5bbf8bff4b-6bwfz 1/1 Running 0 3m58s chiyi-nginx-5bbf8bff4b-bpvvc 1/1 Running 0 3m58s chiyi-nginx-5bbf8bff4b-pwwt4 1/1 Running 0 3m58s扩容测试
kubectl scale deployment chiyi-nginx --replicas=1 kubectl get service,pods,epService 三种常见类型
- ClusterIP 任何节点服务器和集群内部使用 pod 内部可访问
- NodePort 任何节点服务器公网(默认端口范围:3000-32767)IP 浏览器可以访问端口号。
- LoadBalancer 适用于公共云