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.添加rpm源

    先添加下阿里云的epel源

CentOS 6.X:

rpm -Uvh http://mirror.webtatic.com/yum/el6/latest.rpm

CentOS 7.X:

rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm

如果想删除上面安装的包，重新安装

rpm -qa | grep webstatic

rpm -e  上面搜索到的包即可

3.运行yum install安装php

php5.5:

yum install php55w.x86_64 php55w-cli.x86_64 php55w-common.x86_64 php55w-gd.x86_64 php55w-ldap.x86_64 php55w-mbstring.x86_64 php55w-mcrypt.x86_64 php55w-mysql.x86_64 php55w-pdo.x86_64 php55w-fpm php55w-devel

php5.6:

yum install php56w.x86_64 php56w-cli.x86_64 php56w-common.x86_64 php56w-gd.x86_64 php56w-ldap.x86_64 php56w-mbstring.x86_64 php56w-mcrypt.x86_64 php56w-mysql.x86_64 php56w-pdo.x86_64 php56w-fpm php56w-devel

php7.0:

yum install php70w.x86_64 php70w-cli.x86_64 php70w-common.x86_64 php70w-gd.x86_64 php70w-ldap.x86_64 php70w-mbstring.x86_64 php70w-mcrypt.x86_64 php70w-mysql.x86_64 php70w-pdo.x86_64 php70w-fpm php70w-devel