1.查看已经安装的php版本号
键入下面代码：
$ php -v
出现下面代码：
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
2.安装Remi跟EPEL RPM源
如果你还没安装，则输入以下代码：
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
下载之后：
nano /etc/yum.repos.d/remi.repo
然后对里面内容进行以下修改：
[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
还有以下：
[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
按CTRL+O保存，CTRL+X关闭编辑器
3.现在可以yum命令直接升级了
输入以下代码
$yum -y upgrade php*
一旦更新完毕，再次查看php版本号
$php -v
出现以下信息
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
到此，php升级完毕
