>*SM is deterministic: If you need to be able to restore up to one year old
>backups and to any day's state within this year, just apply the following
>settings to your backup copygroup:
>VEREXIST=NOLIMIT VERDELETED=NOLIMIT RETEXTRA=365 RETONLY=365
>
>You think, this approach is too expensive? Well, compared to the
>'old' method, where you retain a lot of full backups, it is probably not.

It's one of those issues of balancing your needs per the requirements of your
site.  Keeping a large number of versions of backups will help assure that you
will be able recover a viable image of some user's corrupted file; but it also
makes recovery of the file system as a whole more time-consuming.  So you have
to balance the need to recover data for some user who hasn't been paying
attention vs. being able to bring back the file system for all the users in it
when the disk fails.
  Richard Sims, BU