hard disk as archive

[Ronald Florence]

I would appreciate advice on using a second hard disk as a backup
device.  (This is not a "mirroring" setup.)  The first hard disk is
divided into two file systems: root and /dev/u.  The second hard disk
is a single system: /dev/archive.  Can and/or should I use the restore
and backup commands?  Cpio?  Or should I use the copy command to
create a copy of the root and /dev/u filesystems on /dev/archive?

Thanks in advance for any suggestions or comments.
-- 

Ronald Florence			...{hsi!aati,rayssd}!mlfarm!ron