On Sun, May 25, 2003 at 03:26:07PM +0800, Mathias K?rber wrote:
> Jon LaBadie <jon@j...> wrote:
> >Could you give an example(s) where it would be a hinderance as opposed
> >to the nuisance of a one-time configuration or of having more DLE's?
> 
> everywhere where a single DLE (ie tar archive) is to contain files which
> reside on seperate filesystem (eg in cases where a new FS has been mounted
> under an existing one to extend space). Not every OS/system makes use of
> volume managers...
> 
> My Imap backup could be such an example. In a really large setup I'd
> likely have /var/imap and /var/spool/imap on diff spindles for speed/space
> reasons.

That is the case of having more DLE's.  Not a real compelling argument IMO.

In fact, our discussiong of the include feature leads me to think you could
do it now.  The --one-file-system option of gnutar eliminates switching
filesystems as it recursively traverses the directory tree from its starting
point.  It does not prevent giving multiple starting points on different
file systems.  Suppose in your current 'imap' scenario that /var, /var/imap,
and /var/spool/imap were three distinct filesystems.  I think you could
back these up in two entries, one for /var, the other for the two imap fs's.

A DLE of /var with no other entries would simply skip the two imap fs's.

A DLE of /var (different tag) which excluded all /var stuff but included
./imap and ./spool/imap would give that DLE two separate starting points
on different filesystems.

OTOH, I may have a mistaken impression of how the include feature works.
I have in the past :(

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
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