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Incremental vs /BEFORE=y/SINCE=x (BACKUP)?

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The Question is:

We are trying to do a "bounded" incremental Backup.  What this means is that we
 want to backup all files since the last backup (/SINCE=BACKUP) but not to the
 current date but up to a specified date (/BEFORE="date").
In the 'traditional' VMS Backup world the /BEFORE clause is ignored when you
 apply the /SINCE=BACKUP qualifier - all files since the last backup are
 captured.  I know you can do a BACKUP/SINCE="date"/BEFORE="date" and that
 works as expected, but we don't
want to extrapolate or guess the last backup date!
I was playing with the /NOINCREMENTAL qualifier, which is new to V7.2.  For
 whatever reason it ***appears*** to recognize the /BEFORE="date" qualifier in
 conjunction with the /SINCE=BACKUP qualifier - it doesn't back up any files
 modified from the /BEFORE
 date to today.
My question to the wizard is this: does the /NOINCREMENTAL qualifier give me
 the "bounded" backup that I desire, or am I just seeing a fluke that just
 happens to match up to my date range?
Personally I'm rather disappointed that VMS Backup does 'selective'
 determination as to whether it ignores the /BEFORE qualifier or not.

The Answer is :

  BACKUP /NOINCREMENTAL is not applicable here.
  The OpenVMS Wizard recommends using the /BEFORE and /SINCE combination,
  or (better) simply using a periodic schedule of /RECORD and /SINCE=BACKUP
  passes.  Remember, you will want to be able to reassemble (restore) your
  BACKUP, and /RECORD and /SINCE=BACKUP (standard incremental BACKUP) can
  do this for you quite easily.

answer written or last revised on ( 20-JUN-2000 )

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