Backups using compress

Chip Salzenberg chip at tct.uucp
Tue Dec 4 04:11:53 AEST 1990


According to brnstnd at kramden.acf.nyu.edu (Dan Bernstein):
>In article <27551FBF.2222 at tct.uucp> chip at tct.uucp (Chip Salzenberg) writes:
>> I would think twice before using this method for backups.  LZW
>> compression (i.e. /usr/bin/compress), like most kinds of compression,
>> is _extremely_ unforgiving of trashed data.  If you lose ONE BYTE, the
>> rest of the archive will probably be lost permanently.
>
>If you want to correct errors, use an error-correcting code.

Sure, error correction is very nice.  But sometimes data are lost,
period, no recourse, from the *middle* of a backup.  And in those
cases, if you've compressed your archive, you're SOL: everthing from
the point of failure to the end of the archive is gone forever.  If
you've compressed individual files, at least you can recover the files
on the untrashed portions of the archive, both before and after the
point of failure.

>Sheesh.

My word(s) exactly.
-- 
Chip Salzenberg at Teltronics/TCT     <chip at tct.uucp>, <uunet!pdn!tct!chip>
      "I'm really sorry I feel this need to insult some people..."
            -- John F. Haugh II    (He thinks HE'S sorry?)



More information about the Comp.unix.questions mailing list