添加Remi的存储库
# rpm -ivh http://rpms.famillecollet.com/enterprise/remi-release-5.rpm
使用Remi的存储库安装PHP5.5（同时安装所需的模块）。
yum install --enablerepo=remi --enablerepo=remi-php55 php php-devel php-mbstring php-mcrypt php-mysql php-phpunit-PHPUnit php-pecl-xdebug php-cli php-common php-gd php-pecl-apc php-pecl-memcache php-xml php-imap php-pear
确认版本
php -v
PHP 5.5.16 (cli) (built: Sep 3 2014 20:08:58)
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.5.0, Copyright (c) 1998-2014 Zend Technologies
with Xdebug v2.2.5, Copyright (c) 2002-2014, by Derick Rethans
重启Apache
/etc/init.d/httpd restart
