On Wed, Mar 26, 2008 at 4:11 AM, Mister Olli <mister.olli AT googlemail DOT 
com> wrote:
>  these 3 command work like a charme (executed for testing, and narrowing
>  down the failure):
>  
> ===============================================================================
>
>  gtar --create --file - --directory /boot --one-file-system
>  --listed-incremental /root/gtar_test/gnutar-lists/172.31.3.9_boot_0.new
>  --sparse --ignore-failed-read --totals --exclude-from
>  /root/gtar_test/sendbackup._boot.20080320110639.exclude . >
>  /root/boot_new.tar

OK: essentially 'gtar --create --file - ..  > output_file'

>  gtar --create --file /root/boot_new.tar --directory /boot --one-file-system
>  --listed-incremental /root/gtar_test/gnutar-lists/172.31.3.9_boot_0.new
>  --sparse --ignore-failed-read --totals --exclude-from
>  /root/gtar_test/sendbackup._boot.20080320110639.exclude .

OK: essentially 'gtar --create --file output_file ..

> gtar --create --file - --directory /boot --one-file-system
> --listed-incremental /root/gtar_test/gnutar-lists/172.31.3.9_boot_0.new
> --sparse --ignore-failed-read --totals --exclude-from
> /root/gtar_test/sendbackup._boot.20080320110639.exclude . | cat
> /dev/null

This doesn't make any sense -- if you give 'cat' a filename, it won't
read from stdin.  What happens here is that cat opens /dev/null for
reading, gets an EOF immediately, and quits.  When cat quits, tar's
stdout is closed, so it gets a SIGPIPE and quits, too, with an error
condition.  Are you sure this worked?  What are your criteria for
"worked"?

>  this is the original command (taken from 'ps aux') how amanda executes
>  gtar, and this one hangs up (or more like hangs up in an endless loop,
>  cause its eating a lot of CPU cycles):
>  
> ================================================================================
>
> gtar --create --file - --directory /boot --one-file-system
> --listed-incremental /root/gtar_test/gnutar-lists/172.31.3.9_boot_0.new
> --sparse --ignore-failed-read --totals --exclude-from
> /root/gtar_test/sendbackup._boot.20080320110639.exclude .

What you don't see from 'ps aux' is that Amanda redirects its output
to a pipe.  If you run the above command on your console, it will fill
your console with junk characters.  Consoles are pretty slow, so it
will definitely take a long time, and will consume a lot of your VM's
CPU cycles.

Please try the following *verbatim* and post the results by simply
copying from your shell session.  Assuming /boot is somewhere under
500M, let any "hung" command run for at least a half-hour before
killing it with control-C.

df -h /boot

gtar --create --file - --directory /boot --one-file-system \
  --listed-incremental /root/gtar_test/gnutar-lists/172.31.3.9_boot_0.new \
  --sparse --ignore-failed-read --totals --exclude-from \
  /root/gtar_test/sendbackup._boot.20080320110639.exclude . \
  | wc -c

gtar --create --file - --directory /boot --one-file-system \
  --sparse --ignore-failed-read --totals --exclude-from \
  /root/gtar_test/sendbackup._boot.20080320110639.exclude . \
  | wc -c

gtar --create --file - --directory /boot --one-file-system \
  --listed-incremental /root/gtar_test/gnutar-lists/172.31.3.9_boot_0.new \
  --sparse --ignore-failed-read --totals . \
  | wc -c

gtar --create --file - --directory /boot --one-file-system \
  --sparse --ignore-failed-read --totals . \
  | wc -c

gtar --create --file - --directory /boot --one-file-system . \
  | wc -c

Dustin

-- 
Storage Software Engineer
http://www.zmanda.com