You must already have Oracle Linux installed on the server.
Choose a method for updating the Oracle Linux operating system:
For Oracle Unbreakable Linux Network (ULN) installations, create
local yum repositories and configure yum and up2date to install update packages
from them.
Note - This yum server is offered without support of any kind. If you
require errata, security patches, and other updates, you should use the Oracle
Unbreakable Linux Network (ULN) at http://linux.oracle.com/Unbreakable Linux Network (ULN).