You should probably look at ADSM from a non-mainframe perspective
     since the basic design was derived from a smaller platform (i.e. who
     writes mainframe utilities using C ?).  It's very important that you
     get a good understanding of various COPYGROUP parms that can affect
     the retention of files, such as VEREXists, VERDeleted, RETExtra and
     RETOnly.  These parms determine how many versions you retain, for how
     long, and what you do with versions of files that were deleted by the
     client.  Choosing the wrong values could result in wasting a lot of
     mainframe disk space and/or tapes (I just went throught the agony of
     re-registering numerous clients).

     Anyway, to answer your other question, the parm RETOnly will determine
     how long your infrequently used file will be kept (assuming it never
     gets deleted by the client).

     One other thing you should be aware of is to make sure the
     EXCLUDE/INCLUDE values are properly specified.  It's too easy to mess
     up and you'll end up backing much more than you bargained for.


  *---------------------------------------------------*
  *  Rick Tsujimoto                                   *
  *                                                   *
  *  rtsujimoto AT cusa.canon DOT com                        *
  *                                                   *
  *  tel: 516-328-4554                                *
  *  fax: 516-328-4369                                *
  *---------------------------------------------------*




______________________________ Reply Separator _________________________________
Subject: Incremental vs Full Backups
Author:  "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU> at ~internet
Date:    5/23/96 8:31 PM


We are in the process of implementing ADSM for the first time in our shop
and I'm trying to clear up some confusion on our part re: backups.  We
come from a mainframe environment where we do weekly 'full' backups of
datasets (backup all files in the shop) and daily 'incrementals' (backup
only files changed since the last backup).  If we need to recover our
system we restore the latest backup of a dataset which is, at most, only a
week old.

In ADSM we see only incremental backups.  Granted the first backup is truly
a 'Full' since nothing has been backed up prior.  If a file does not get
updated periodically it won't be backed up again.  The concern is how long
we must keep backups to guarantee there being an available means to recover
a file that, e.g., may be read only or updated very infrequently.

Any feedback would be helpful.  Do we need to look at this from a totally
different perspective than the mainframe world?