在旧版的Ubuntu14.04上运行apt-get upgrade时，Apache2出现了错误。

sudo service apache2 restart
 * Restarting web server apache2                                                                                                        [fail] 
 * The apache2 configtest failed.
Output of config test was:
apache2: Syntax error on line 21apache20 of /etc/apache2/apache2.conf: Syntax error on line 1 of /etc/apache2/mods-enabled/php5.load: Cannot load /usr/lib/apache2/modules/libphp5.so into server: /usr/lib/apache2/modules/libphp5.so: cannot open shared object file: No such file or directory
Action 'configtest' failed.
The Apache error log may have more information.

「apache2错误，无法打开配置文件/etc/apache2/conf.d/：找不到文件或目录 – Ask Ubuntu」

参考这个后，进行以下操作。

生成 httpd.conf 文件

$ cd /etc/apache2
$ sudo touch httpd.conf

生成conf.d文件夹

而且，

$ sudo service apache2 restart
 * Restarting web server apache2                                                                                                        [fail] 
 * The apache2 configtest failed.
Output of config test was:
apache2: Syntax error on line 234 of /etc/apache2/apache2.conf: Could not open configuration file /etc/apache2/conf.d/: No such file or directory
Action 'configtest' failed.
The Apache error log may have more information.

由于这个问题出现了，所以采取了以下措施。

$ sudo mkdir conf.d

进行了行动

$ sudo service apache2 restart
 * Restarting web server apache2                                                                                                               AH00112: Warning: DocumentRoot [/home/sensho-ds/public_html] does not exist
                                                                                                                                        [ OK ]
$