转载自：http://blog.csdn.net/yuguanquan1990/article/details/18193201

安装MySQL-Server时，需要卸载掉mysql-libs， 但是卸载安装之后会发现，postfix无法启动了，找了很多原因都没有找到原因，后面索性卸载了然后再安装，安装时，发现了postfix有一个依赖包就是mysql-libs ，postfix一直无法安装，于是寻求安装mysql-libs的方法，后面在一个国外的网站上找到了解决方法http://stackoverflow.com/questions/17531173/installing-mysql-libs-on-server-with-mysql-server5-5

原文解释是：

Well, this is a common problem with MySQL packages within CentOS 6. Yum is trying to satisfy requirements by installing mysql-libs-5.1.69-1.el6_4.x86_64. This package conflicts with files from package MySQL55-server-5.5.32-1.cp1136.x86_64.

There is a way to fix this without breaking your rpm database or uninstalling mysql55, just download mysql compatibility libs from mysql for el6 (CentOS and RHEL6 are full binary compatible). Get MySQL-shared-compat-5.5.32-2.el6.x86_64.rpm (just google for it) and install this rpm using: rpm -ihv MySQL-shared-compat-5.5.32-2.el6.x86_64.rpm.

After this you can install ReviewBoard without yum trying to install mysql51 libs for satisfying dependencies.

我就先安装了MySQL-shared-compat-，不同版本后缀不同，之后可以正常安装mysql-libs，我是 yum install mysql-libs， 然后yum install postfix；