The tape drive I'm using for backups doesn't do hardware compression
and the size of the backups has now outgrown it's capacity.
Maybe next year I'll have funds for a larger capacity device but in
the meantime I'm tempted to use either the compress option to vdump
or pipe vdump through gzip or bzip2.
If a single bit changes on an uncompressed vdump, then presumably
you can recover everything but the damaged file which will have
one byte changed.
If a single bit changes on a compressed vdump what are the chances of
recovering any (or preferably most) of the data?
With bzip2 you can (in theory) recover all blocks except the damaged
one but will vrestore be able to recover from an image with a hole
in it?
I'm thinking maybe tar piped through bzip2 using a small compression
block size might be the safest.
Is anyone else using compressed backups and if so what's your experience
of recovering from damaged images?
Thanks
Ian
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
_/ Ian Mortimer _/
_/ ian_at_physics.uq.edu.au ,-_|\ Department of Physics _/
_/ Tel: +61 7 3365 3436 / *\ University of Queensland _/
_/ Fax: +61 7 3365 1242 \_,-._/ St. Lucia, Brisbane _/
_/ v Queensland, Australia 4072 _/
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Disclaimer: Speaking only for myself.
Received on Thu Jul 19 2001 - 02:08:11 NZST