Pod存活性探测

Pod存活性探测：用于判断容器是否处理"运行"状态，如果检测未通过，kubelet将会终止容器，根据启动策略(restartPolicy)决定是否重启，如果未定义容器默认为"Success"。存活性探测支持的方法有三种:ExecAction，TCPSocketAction，HTTPGetAction。

1.使用exec探测文件存在

[root@k8s01 yaml]# kubectl explain pods.spec.containers.livenessProbe

[root@k8s01 yaml]# vim execaction.yaml

apiVersion: v1kind: Podmetadata:  labels:    test: exec-execaction  name: execactionspec:  containers:  - name: execaction    image: busybox:latest    args: ["/bin/sh","-c","touch /tmp/test.txt"]        --容器启动后创建test.txt文件    livenessProbe:      exec:        command: ["test","-e","/tmp/test.txt"]      --检查test.txt文件，如果存在Pod正常启动，如果不存在Pod创建不成功

[root@k8s01 yaml]# kubectl apply -f execaction.yaml

pod/execaction created

[root@k8s01 yaml]#

2.使用tcp协议探测端口

[root@k8s01 yaml]# vim tcpaction.yaml

apiVersion: v1kind: Podmetadata:  labels:    test: tcp-execaction  name: tcpactionspec:  containers:  - name: tcpaction    image: nginx:latest    ports:    - name: http      containerPort: 80    --暴露80端口    livenessProbe:         tcpSocket:      --使用tcp探测        port: http    --这里可以写协议或者端口，http默认为80端口

[root@k8s01 yaml]# kubectl apply -f tcpaction.yaml
pod/tcpaction created
[root@k8s01 yaml]#

3.使用http协议探测服务

[root@k8s01 yaml]# vim httpaction.yaml

apiVersion: v1kind: Podmetadata:  labels:    test: http-execaction  name: httpactionspec:  containers:  - name: httpaction    image: nginx:latest    ports:    - name: http      containerPort: 80    lifecycle:      postStart:     --容器启动之前启动以下命令        exec:          command: ["/bin/sh","-c","echo 123 > /usr/share/nginx/html/test.html"]    livenessProbe:      httpGet:        path: /test.html    --探测nginx是否正常访问test.html页面        port: http

[root@k8s01 yaml]# kubectl apply -f httpaction.yaml
pod/httpaction created
[root@k8s01 yaml]#