The yum command has history option on the latest version of CentOS / RHEL v6.x+. To database are normally found in /var/lib/yum/history/ directory. The history option was added at the the end of 2009 (or thereabouts) to yum command. The history command allows an admin to access detailed information on the history of yum transactions that have been run on a system. You can see what has happened in past transactions (assuming the history_record config option is set). You can use various command line options to view what happened, undo/redo/rollback to act on that information and start a new history file.