修改 /etc/apache2/apache2.conf :
开发版 :
170 <Directory /var/www/>
171 SetEnv CI_ENV development
172 Options FollowSymLinks
173 AllowOverride ALL
174 Require all granted
175 </Directory>
产品版 :
170 <Directory /var/www/>
171 SetEnv CI_ENV production
172 Options FollowSymLinks
173 AllowOverride ALL
174 Require all granted
175 </Directory>
