We can add it easily into configure.in to include a new configure option
"--with-bzip2" to enable bzip2 instead of gzip. If you know how to work
with autoconf tools and how to modify configure.in then feel free to add it
in yourself.
I'm currently working on a small project for Amanda and I could add it in
for you if there are enough interest from everybody else. Unless J.R.
Jackson wants to do that himself. :-)
Josh
John Goerzen wrote:
>
> Hi,
>
> I'd like to use bzip2 with amanda for two reasons:
>
> 1. It compresses a lot better than gzip
>
> 2. More importantly -- data recovery is possible from a damaged tape.
>
> >From bzip2's manual:
>
> bzip2 compresses files in blocks, usually 900kbytes long. Each
> block is handled independently. If a media or transmission error
> causes a multi-block .bz2 file to become damaged, it may be
> possible to recover data from the undamaged blocks in the file.
>
> The compressed representation of each block is delimited by a
> 48-bit pattern, which makes it possible to find the block
> boundaries with reasonable certainty. Each block also carries
> its own 32-bit CRC, so damaged blocks can be distinguished from
> undamaged ones.
>
> With gzip and compress, in general, once a media error is encountered,
> the entire remainder of the file (tar or dump in our case) is
> unusable. This is why people generally shun gzip/compress for
> backups, unless it's done on a per-file basis to lessen the severity
> of errors. Of course, doing it on a per-file basis also lessens the
> effectiveness ofcompression. The only tradeoff with bzip2 is CPU
> time: it is more CPU-intensive than gzip or compress. However, when
> reliability of backups is at stake, that's a tradeoff I'm quite
> willing to take,
>
> In amanda, the configuration file seems to think that the user isn't
> smart enough to manually specify a compression program :-) I'd much
> rather specify "gzip -9" and "gunzip" than specify "best compression"
> or whatnot. Are there any plans to support this? If there were, it
> would be trivial to drop in bzip2 instead of gzip with amanda.
>
> Are there any plans to support this? I suppose I could just go into
> the code with sed and s/gzip/bzip2/ but I'd prefer to do it more
> elegantly if possible :-)
>
> -- John
>
> --
> John Goerzen <[EMAIL PROTECTED]> www.complete.org
> Sr. Software Developer, Progeny Linux Systems, Inc. www.progenylinux.com
> #include <std_disclaimer.h> <[EMAIL PROTECTED]>
