tomcat - kubernetes redinessProbe httpGet on tomcat 图像报告连接被拒绝

Question

我正在使用 initContainer 挂载 index.html 并将其挂载在 tomcat 9 服务器中。 readinessProbe , 输入:httpGet初始延迟秒数:60。

没有 readinessProbe，应用程序启动，我可以访问 Url 并查看内容。

kubectl describe pod/<pod-->提供以下消息

 Normal   Created    104s               kubelet, worker1.com  Created container tomcat-container
 Normal   Started    104s               kubelet, worker1.com  Started container tomcat-container
 Warning  Unhealthy  10s (x4 over 40s)  kubelet, worker1.com  Readiness probe failed: Get http://localhost:8080/temp/index.html: dial tcp [::1]:8080: connect: connection refused

当我执行到容器中并执行 curl 命令时，没有就绪探测，我看到了响应。

apiVersion: apps/v1
kind: Deployment
metadata:
  name: tomcat-deployment
spec:
  replicas: 1
  selector:
    matchLabels:
     app: tomcat
  template:
    metadata:
      labels:
        app: tomcat
        role: rolling-update
    spec:
      volumes:
      - name: shared-volume
        emptyDir: {}
      initContainers:
      - name: busybox
        image: busybox
        volumeMounts:
        - name: shared-volume
          mountPath: /app-data/temp
        command: ["/bin/sh"]
        args: ["-c","echo '<h1>hellow from k8s!</h1>' > /app-data/temp/index.html"]

      containers:
      - name: tomcat-container
        image: tomcat:9.0
        # command: ["/bin/bash"]
        # args: ["-c","mkdir -p /usr/local/tomcat/webapps/temp; touch index.html"]
        volumeMounts:
        - name: shared-volume
          mountPath: /usr/local/tomcat/webapps/temp
        ports:
        - containerPort: 8080
        readinessProbe:
          initialDelaySeconds: 60
          httpGet:
            host: localhost
            path: /temp/index.html
            port: 8080
        #  exec:
        #    command:
        #      - curl
        #      - http://localhost:8080/temp/index.html
  strategy:
    type: RollingUpdate
    rollingUpdate:
       maxSurge: 2
       maxUnavailable: 1
---
kind: Service
apiVersion: v1
metadata:
  name: tomcat-service
spec:
  selector:
    app: tomcat
  type: NodePort
  ports:
  - protocol: TCP
    port: 8080
    targetPort: 8080
    nodePort: 30080

readinessProbe exec: 命令有效，pod 已成功启动。

问题: 任何输入为什么 httpGet 就绪在这种情况下不起作用。

来自容器的日志:

27-Jun-2020 22:41:17.709 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dignore.endorsed.dirs=
27-Jun-2020 22:41:17.710 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.base=/usr/local/tomcat
27-Jun-2020 22:41:17.710 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.home=/usr/local/tomcat
27-Jun-2020 22:41:17.711 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.io.tmpdir=/usr/local/tomcat/temp
27-Jun-2020 22:41:17.711 INFO [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent Loaded Apache Tomcat Native library [1.2.24] using APR version [1.6.5].
27-Jun-2020 22:41:17.711 INFO [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].
27-Jun-2020 22:41:17.712 INFO [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR/OpenSSL configuration: useAprConnector [false], useOpenSSL [true]
27-Jun-2020 22:41:17.747 INFO [main] org.apache.catalina.core.AprLifecycleListener.initializeSSL OpenSSL successfully initialized [OpenSSL 1.1.1d  10 Sep 2019]
27-Jun-2020 22:41:23.913 INFO [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["http-nio-8080"]
27-Jun-2020 22:41:24.324 INFO [main] org.apache.catalina.startup.Catalina.load Server initialization in [9,608] milliseconds
27-Jun-2020 22:41:25.112 INFO [main] org.apache.catalina.core.StandardService.startInternal Starting service [Catalina]
27-Jun-2020 22:41:25.119 INFO [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet engine: [Apache Tomcat/9.0.36]
27-Jun-2020 22:41:25.194 INFO [main] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [/usr/local/tomcat/webapps/temp]
27-Jun-2020 22:41:27.980 INFO [main] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [/usr/local/tomcat/webapps/temp] has finished in [2,766] ms
27-Jun-2020 22:41:28.100 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-nio-8080"]
27-Jun-2020 22:41:28.286 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in [3,960] milliseconds

Answer 1

Exec 之所以有效，是因为它是在 localhost:8080 可用的容器中执行的。 但是 httpGet 是由 Kubelet 执行的。 因此，当主机指定为 localhost 时，它会尝试连接到节点上的端口 8080。因此失败。

请删除探测中的“host: localhost”，以便它默认为 pod ip 并按预期工作。