Brendan Pratt wrote:
>
> Hi Christian,
>
> ----- Original Message -----
> From: Christian Brandt <[EMAIL PROTECTED]>
>
> > > Now, first you compress the tar archive. That is *bad*.
> > > If you get just a single bit error (it should not happen,
> > > but it will once you need the backup!) ... you will loose
> > > every file and directory after the bit error.
> >
> > Use bzip2 instead of gzip - it operates with blocks and if you loose a
> > single bit, you only loose one bzip2-block, which is around 900k of
> > compressed data.
> > I also like to have a checksum over my backup and bzip2 fits well for
> > that, too. There is one thing even worse than a lost backup: a backup
> > with badly wrong restored data which you are not even aware of.
>
> Forgive my ignorance, but could you kindly show us example command lines on
> how you backup, compare, and restore please??
>
> This bzip2 'safer' compression is interesting, particulary with a TR-3
> tape/s and 10 Gig drive, which means less tapes to back it all up.
>
> Thanks in advance.
No problem:
with gnutar 11.* tar -cvIf big.tar.bz2 bigstuff/
with other tars use tar --use-compress-program=bzip2 -cvf big.tar.bz2 bigstuff/
a somewhat more efficient approach for tapes:
tar -cvf - bigstuff/ | bzip2 | buffer -o /dev/tape -m16m -p90
will doublebuffer the output with a 16MB cache.
Greetings,
Christian
