In CentOS website, there is a warning about using EPEL:

...So, make SURE you are using the Priorities yum plugin if you are using EPEL...


Below are the steps to install and set the correct priorities:

CentOS 5: yum install yum-priorities
CentOS 6: yum install yum-plugin-priorities


nano /etc/yum/pluginconf.d/priorities.conf

make sure the plugin is enabled

nano /etc/yum.repos.d/CentOS-Base.repo

Set highest priority for [base] [updates] and [extra] by adding priority=1 at the end of each part.


If you are using virtualmin repo, makesure the priority for the repo is set to 1 as well.