On Tue, 1 Feb 1994 15:52:15 GMT Smith, Dean said:
>                                                        How much will this new
>feature cost?  We'll all have to bear the cost (IBM does not work for free),

If the addition of this feature allows IBM to sell it to more customers, then
there should be no need to increase ADSM's price.

>                                           In my conversations with the ADSM
>developers they admit that they do not have any clear purpose in mind for the
>ARCHIVE function.  Rather, they acknowledge that there are cases for user
>managed backup/restore.

In researching this, I found out that ARCHIVE/RETRIEVE does not preserve
symbolic links on Unix systems.  This makes ARCHIVE unsuitable for doing
snapshot backups for the purpose of later point-in-time restores.

>                                             If I was planning on doing some
>thing stupid that might result in the complete corruption of my disk (as was
>cited for a reason for point-in-time) then I would do an incremental backup.
>If the worst came true I don't need a point-in-time backup.

If you determine that you need to restore your disk quickly enough (before
another incremental backup has occurred), then restoring from the last
incremental backup is satisfactory.  However, if you do not detect the
problem until after one or more incremental backups have occurred, then
restoring from the last backup is not satisfactory.  This is where point-
in-time restores are needed.

I will re-visit the examples cited, as I think they are still valid, and cite
a couple new ones.

1) Viruses.  Virus protection software is great.  But it's not guaranteed.
   Virus software must continuously be updated to protect against the latest
   viruses.  You can never protect yourself against all viruses.

2) Unix hackers.  It's tremendously expensive to protect yourself against
   unix hackers.  If you follow the CERT advisories, there are continually
   new security holes being detected in Unix.

3) Software bugs.  Any kind of software application running on your system
   has the potential for going bad in manner which is not immediately
   detectable.  If files are corrupted, but this is not detected until days
   later, then point-in-time restores would be useful to recover from this.

4) Human error.  Humans make mistakes.  They don't always detect them right
   away.  If days pass before the problem is detected, then a point-in-time
   restoral would be very useful to recover from this.

..Paul