Here is what I did to perform it using Yum:
First, make sure that the downloaded packages are cached in server A, that is, they are not deleted after the installation. To do that become root and type
And edit the line starting with keepcache, make sure that it is like this:
Note your cachedir there.
It is defined as
It is expanded in my system as:
Now, whenever you use yum from command line or GUI, the downloaded packages can be found there and copied freely.