此文,老徐实操所用的Linux发行版 centos 6.x
1. 添加php 5.6版本的源
CentOs 6.x
rpm -Uvh http://mirror.webtatic.com/yum/el6/latest.rpm
CentOs 7.X
rpm -Uvh https://mirror.webtatic.com/yum/el7/epel-release.rpm
rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm
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