linux: centos download rpm packages from yum

installing services via yum doesn't secure me a copy of the packages i need to do similar setups on a box that is not online. one solution is to save rpm packages downloaded by yum. to do that you'll need yum-downloadonly package

# yum install yum-downloadonly

then to save the rpms, do:

# yum install <package> -y --downloadonly

note: you should have the packages uninstalled before yum can download them