I would simplify the discussion.  With what you have set up, you can
guarantee to your users that you will be able to get any file back up to
seven days.  That is, if a file changes everyday, you can get the most
recent seven changes.  If the file stops changing, you might be able to get
a file back that was 30 days old if the original file is still on the system
and 60 days if it was deleted.

I think this is too complicated for most folks to understand (not us
brilliant TSMers, mind you, but the huddled masses yearning to be free).  So
I would rather set my policy to something like 30, 30, 30, 30.  That way,
with daily incrementals, I can say that I can get back any file for 30 days.
Period.  I might change the retain only to some larger number but really, if
a file is deleted, how often does someone want it back after 30 days anyway.

This approach works up to 90, 90, 90, 90, but I think starts getting a bit
space hungry after that.  If you have the need to retain data for longer,
consider doing an archive instead.  And, no, you don't need to archive
everything.   Get your people to understand what an archive is and what
should be archived.  Then get that and only that!

BTW, overall, your statements are correct.  However, I'm thinking your
end-user's eyes are going to glaze over when you try to tell them.  Also,
there are some open files that TSM will not backup no matter the
serialization parameter so beware of that.

Thanks,

Kelly J. Lipp
Storage Solutions Specialists, Inc.
PO Box 51313
Colorado Springs CO 80949-1313
(719) 531-5926
Fax: (240) 539-7175
Email: lipp AT storsol DOT com or lipp AT storserver DOT com
www.storsol.com
www.storserver.com