1、检查当前安装的php包
yum list installed | grep php
如果有安装的php包，先删除他们
yum remove php.x86_64 php-cli.x86_64 php-common.x86_64 php-gd.x86_64 php-ldap.x86_64 php-mbstring.x86_64 php-mcrypt.x86_64 php-mysql.x86_64 php-pdo.x86_64
2、配置yum源（6.8版本）
rpm -uvh http://ftp.iij.ad.jp/pub/linux/fedora/epel/6/x86_64/epel-release-6-8.noarch.rpmrpm -uvh http://rpms.famillecollet.com/enterprise/remi-release-6.rpmyum源（7.0版本）yum install epel-releaserpm -ivh http://rpms.famillecollet.com/enterprise/remi-release-7.rpm
3、安装php5.6.x
yum install --enablerepo=remi --enablerepo=remi-php56 php php-opcache php-devel php-mbstring php-mcrypt php-mysqlnd php-phpunit-phpunit php-pecl-xdebug php-pecl-xhprof
用php命令查看版本：
# php --versionphp 5.6.0 (cli) (built: sep 3 2014 19:51:31)copyright (c) 1997-2014 the php groupzend engine v2.6.0, copyright (c) 1998-2014 zend technologieswith zend opcache v7.0.4-dev, copyright (c) 1999-2014, by zend technologieswith xdebug v2.2.5, copyright (c) 2002-2014, by derick rethans
4、安装php-fpm
yum install --enablerepo=remi --enablerepo=remi-php56 php-fpm
推荐教程：php视频教程
以上就是centos怎么更新php的详细内容。