I would very much suggest using ssh and scp instead of these archaic services that have huge security implications. Both "ssh" and "scp" are drop in replacements and work in very similar ways. If, however, you want password-less shell access or copying, you will need to carry out further steps. If you definitely want to run rsh and rcp you need to install the rsh and rsh-server rpm's from the RHEL install CD's (You may optionally need the xinetd rpm as well).