On Thu, Sep 23, 2004 at 03:01:35PM -0500, Ivan Petrovich wrote:
> Jon,
> 
> > But consider a DLE that did not backup with a level 0 on
> > the last run, but had a level 0 two runs ago.  It would
> > have that level 0 plus one incremental after it.  The three
> > older incrementals would not have a level 0 to recover from
> > and thus have relatively little value.
> 
> But why would more level 0's give you more _real_ "value" if amrecover
> takes care of which tape to go to for the files that you request?
> 
> If I were to need to restore the entire file system, then certainly
> restoring from one single level 0 tape would be more convenient than
> to restore from one level 0 plus several level 1 and level 2
> tapes. But in the case of restoring only several files, which is
> generally the case, as long as all changed files are backed
> up somewhere, the only difference is to locate the right tape for
> the files needed. Right?

Hypothetical -- I just checked, my root FS has 100,000 files.
My level 0 of the / DLE thus is 100000 files.  Guessing that
on any one day, maybe 1000 change and appear in incremental
backups.  If I do a level 0, then three incrementals,
WITHOUT the level 0 I only have a 3 in 100 chance the file
I need might be in the incrementals.  When you come around on
your tapecycle, you will be overwriting that level 0.  The
more level 0's you have, the better chance that the file(s)
you need will be on a tape somewhere.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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