我按照步骤 https://www.digitalocean.com/community/tutorials/how-to-install-apache-tomcat-8-on-ubuntu-16-04安装tomcat 8.5.24在 Ubuntu 16.04 上，直到运行 sudo ufw allow 8080在“第 6 步:调整防火墙并测试 Tomcat 服务器”中。

然后我无法启动tomcat，

$ sudo systemctl start tomcat 
Job for tomcat.service failed because the control process exited with error code. See "systemctl status tomcat.service" and "journalctl -xe" for details. 

和链接 http://localhost:8080/不适用于 firefox 和 google chrome 浏览器。

我想知道如何解决这个问题。

以下详细信息是我遵循上述 sudo systemctl start tomcat的输出消息.看来 /opt/tomcat/bin/startup.sh成功，而 /opt/tomcat/bin/shutdown.sh失败的。非常感谢您的帮助!

$ systemctl status tomcat.service 
● tomcat.service - Apache Tomcat Web Application Container 
   Loaded: loaded (/etc/systemd/system/tomcat.service; disabled; vendor preset: enabled) 
   Active: activating (auto-restart) (Result: exit-code) since Fri 2017-12-01 18:55:30 EST; 2s ago 
  Process: 19490 ExecStop=/opt/tomcat/bin/shutdown.sh (code=exited, status=1/FAILURE) 
  Process: 19478 ExecStart=/opt/tomcat/bin/startup.sh (code=exited, status=0/SUCCESS) 
 Main PID: 19440 (code=exited, status=127) 
 
Dec 01 18:55:30 ocean systemd[1]: tomcat.service: Control process exited, code=exited status=1 
Dec 01 18:55:30 ocean systemd[1]: Failed to start Apache Tomcat Web Application Container. 
Dec 01 18:55:30 ocean systemd[1]: tomcat.service: Unit entered failed state. 
Dec 01 18:55:30 ocean systemd[1]: tomcat.service: Failed with result 'exit-code'. 
 
$ journalctl -xe 
 
-- Unit tomcat.service has begun starting up. 
Dec 01 18:51:24 ocean startup.sh[18873]: Existing PID file found during start. 
Dec 01 18:51:24 ocean startup.sh[18873]: Removing/clearing stale PID file. 
Dec 01 18:51:24 ocean startup.sh[18873]: Tomcat started. 
Dec 01 18:51:24 ocean shutdown.sh[18885]: PID file found but no matching process was found. Stop aborted. 
Dec 01 18:51:24 ocean systemd[1]: tomcat.service: Control process exited, code=exited status=1 
Dec 01 18:51:24 ocean systemd[1]: Failed to start Apache Tomcat Web Application Container. 
-- Subject: Unit tomcat.service has failed 
-- Defined-By: systemd 
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel 
--  
-- Unit tomcat.service has failed. 
--  
-- The result is failed. 
Dec 01 18:51:24 ocean systemd[1]: tomcat.service: Unit entered failed state. 
Dec 01 18:51:24 ocean systemd[1]: tomcat.service: Failed with result 'exit-code'. 
Dec 01 18:51:34 ocean systemd[1]: tomcat.service: Service hold-off time over, scheduling restart. 
Dec 01 18:51:34 ocean systemd[1]: Stopped Apache Tomcat Web Application Container. 
-- Subject: Unit tomcat.service has finished shutting down 
-- Defined-By: systemd 
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel 
--  
-- Unit tomcat.service has finished shutting down. 
Dec 01 18:51:34 ocean systemd[1]: Starting Apache Tomcat Web Application Container... 
-- Subject: Unit tomcat.service has begun start-up 
-- Defined-By: systemd 
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel 
--  
-- Unit tomcat.service has begun starting up. 
Dec 01 18:51:35 ocean startup.sh[18896]: Existing PID file found during start. 
Dec 01 18:51:35 ocean startup.sh[18896]: Removing/clearing stale PID file. 
Dec 01 18:51:35 ocean startup.sh[18896]: Tomcat started. 
Dec 01 18:51:35 ocean shutdown.sh[18908]: PID file found but no matching process was found. Stop aborted. 
Dec 01 18:51:35 ocean systemd[1]: tomcat.service: Control process exited, code=exited status=1 
Dec 01 18:51:35 ocean systemd[1]: Failed to start Apache Tomcat Web Application Container. 
-- Subject: Unit tomcat.service has failed 
-- Defined-By: systemd 
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel 
--  
-- Unit tomcat.service has failed. 
--  
-- The result is failed. 
Dec 01 18:51:35 ocean systemd[1]: tomcat.service: Unit entered failed state. 
Dec 01 18:51:35 ocean systemd[1]: tomcat.service: Failed with result 'exit-code'. 

我的 Java 版本是

$ java --version 
java 9.0.1 
Java(TM) SE Runtime Environment (build 9.0.1+11) 
Java HotSpot(TM) 64-Bit Server VM (build 9.0.1+11, mixed mode) 
 
$ javac --version 
javac 9.0.1 

更新:

而不是 sudo systemctl start tomcat如果我运行，它会给出上面的错误

cd /opt/tomcat/bin 
 
sudo ./catalina.sh run 

http://localhost:8080/显示正确的网页。那么一个不起作用而另一个起作用的原因是什么？

请您参考如下方法:

成为用户 Tomcat 整个 tomcat 目录的所有者:
cd /opt && sudo chown -R tomcat tomcat/