Did you try to rsync and get lots of warnings because it can't change the owner or
the group ? This is caused by the fact that the rsync servers have a user id as owner
that doesn't exists on your system. Same goes for the group.
So if you want to have the verbose -v and no warnings you will need to use the
--no-o meaning no owner
--no-g meaning no group
This tells rsync on your server not to preserve the above
rsync -avz --no-g --no-o rsync://centos.mirror/centos/5/os/i386/ /my/repo