我试图在我的 ubuntu 18.04 上创建一个 Web 服务器，所以我安装了 Apache2，但我无法启动它。这是我运行systemctl status apache2.service命令时出现的内容
apache2.service - The Apache HTTP Server
Loaded: loaded (/lib/systemd/system/apache2.service; enabled; vendor preset: enabled)
Drop-In: /lib/systemd/system/apache2.service.d
??apache2-systemd.conf
Active: failed (Result: exit-code) since Sat 2020-02-22 13:58:09 CET; 34s ago
Process: 2791 ExecStart=/usr/sbin/apachectl start (code=exited, status=1/FAILURE)
Feb 22 13:58:09 moemen apachectl[2791]: AH00558: apache2: Could not reliably determine the server's
Feb 22 13:58:09 moemen apachectl[2791]: (98)Address already in use: AH00072: make_sock: could not b
Feb 22 13:58:09 moemen apachectl[2791]: (98)Address already in use: …我正在这个本地分支 X 上工作，当我尝试使用错误消息进行推送时，git push -u origin X
错误消息是：
! [rejected] X -> X (non-fast-forward)
error: failed to push some refs to "********"
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.
所以我运行：git pull
并且还出现错误消息：
There is no tracking information for the current branch.
Please specify which …