apt-get install apache2-mpm-prefork
下列套件将会被【移除】：
apache2-mpm-worker (<- the package will be remove)
下列【新】套件将会被安装：
apache2-mpm-prefork (<- the package will be install)
sudo apt-get purge libapache2-mod-php5
sudo apt-get install libapache2-mod-php5
sudo a2enmod php5
sudo service apache2 restart
详细请参考
http://f3.twbbs.org/debian_ddos_persist_online.html