在Docker内启动tomcat时无法在端口8080上打开网页

Question

在我的本地计算机 Windows 10（64 位）上，我启动了 docker Toolbox。然后我拉 Tomcat 图像并像这样运行它：

docker run -it tomcat

成功了。

31-Dec-2019 17:54:27.598 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [/usr/local/tomcat/webapps/ROOT]
31-Dec-2019 17:54:28.849 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [/usr/local/tomcat/webapps/ROOT] has finished in [1,246] ms
31-Dec-2019 17:54:28.851 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [/usr/local/tomcat/webapps/host-manager]
31-Dec-2019 17:54:29.029 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [/usr/local/tomcat/webapps/host-manager] has finished in [178] ms
31-Dec-2019 17:54:29.031 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [/usr/local/tomcat/webapps/docs]
31-Dec-2019 17:54:29.128 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [/usr/local/tomcat/webapps/docs] has finished in [90] ms
31-Dec-2019 17:54:29.129 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [/usr/local/tomcat/webapps/manager]
31-Dec-2019 17:54:29.251 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [/usr/local/tomcat/webapps/manager] has finished in [122] ms
31-Dec-2019 17:54:29.254 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [/usr/local/tomcat/webapps/examples]
31-Dec-2019 17:54:30.480 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [/usr/local/tomcat/webapps/examples] has finished in [1,226] ms
31-Dec-2019 17:54:30.499 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-nio-8080"]
31-Dec-2019 17:54:30.592 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["ajp-nio-8009"]
31-Dec-2019 17:54:30.621 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 3185 ms

但是当我打开浏览器并输入时

http://127.0.0.1:8080/

但找不到页面

为什么？

Answer 1

@DavidMaze 是对的：在您描述的情况下，同时存在几个问题（至少两个，也许更多，见下文），每个问题都单独阻止 Windows 主机上的浏览器访问部署在 Docker 中的 Web 应用程序容器：

1. Web 应用程序需要监听 0.0.0.0 特殊 IP 地址（不是 localhost）。
2. docker run 的-p (--publish) 选项是必需的。假设 web 应用监听 8080 端口，然后将此暴露的端口发布到主机上的 80 端口：docker run -p 80:8080 […]（但两个端口可以相同）
3. 最后，当您在 Windows 上使用 Docker Toolbox 时，您需要确定 Web-app 可用的 Docker Machine IP（不是localhost）：如果 Docker Toolbox 在启动时不直接显示此信息，您可以想跑：docker-machine ip dev。

更多详情

• 关于项目 1. 2.，另见How to convert a Spring-Boot web service into a Docker image?
• 关于第 3 项，参见例如Can't access Spring Boot with my docker image
• （虽然这些线程处理的是 Spring-Boot，但细节很笼统）