ah00558: apache2: could not reliably determine the server's fully qualified domain name, using 127.0.1.1. set the 'servername' directive globally to suppress this message 

出现以上情况只要修改一下Apache的配置文件即可：

在配置文件 apache2.conf里面加入一行

 ServerName localhost:80

 然后重启Apache服务就可以了

sudo /etc/init.d/apache2 restart