CentOS6 默认php版本是5.3，如果升级到5.6话可以参考本页内容，支持Apache和PHP-FPM

一 检查php版本

php -v

结果

PHP 5.3.3 (cli) (built: Jul 9 2015 17:39:00) 
Copyright (c) 1997-2010 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies

二 安装Remi和EPEL RPM repositories

wget https://dl.fedoraproject.org/pub/epel/epel-release-latest-6.noarch.rpm && rpm -Uvh epel-release-latest-6.noarch.rpm
wget http://rpms.famillecollet.com/enterprise/remi-release-6.rpm && rpm -Uvh remi-release-6*.rpm

配置REMI repository

vi /etc/yum.repos.d/remi.repo

找到[remi]修改为

[remi]
name=Remi's RPM repository for Enterprise Linux 6 - $basearch
#baseurl=http://rpms.remirepo.net/enterprise/6/remi/$basearch/
mirrorlist=http://rpms.remirepo.net/enterprise/6/remi/mirror
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-remi

在下面再追加一行 [remi-php56]

[remi-php56]
name=Remi's PHP 5.6 RPM repository for Enterprise Linux 6 - $basearch
#baseurl=http://rpms.remirepo.net/enterprise/6/php56/$basearch/
mirrorlist=http://rpms.remirepo.net/enterprise/6/php56/mirror
# WARNING: If you enable this repository, you must also enable "remi"
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-remi

三 进行PHP的版本升级

yum -y upgrade php*

完成之后查看php版本

php -v

应该会看到

PHP 5.6.14 (cli) (built: Sep 30 2015 14:07:43) 
Copyright (c) 1997-2015 The PHP Group
Zend Engine v2.6.0, Copyright (c) 1998-2015 Zend Technologies