[Help-tar] multivolume extract from non-first archive

[Sam George]

Greetings.

I'm trying to extract data from multivolume archives without starting at 
the first archive.

The data is on a stand alone network drive which only speaks CIFS and 
has a file size limitation of 2GB.  So I have created my backups by 
instructing tar to split its archive into 2GB chunks like so:

tar c -L 2000000 --format=posix \
  $(seq -f"--file=v%g.tar" -s" " 1 250) \
  /home

It takes several days to complete.  Extracting takes a similar length of 
time.  Naturally, if I want to pull something from near the end I'd 
rather not wait for three or four days.  So (after finding the 
appropriate archive chunk) I tried:

address@hidden:/
 10 # tar vx -M $(seq -f"--file=/mnt/backup/v%g.tar" -s" " 146 148)
/home/share/D60/725CANON/CRW_2526.CRW
tar: /home/share/D60/725CANON/CRW_2526.CRW: Cannot extract -- file is 
continued from another volume
tar: Skipping to next header
tar: Error exit delayed from previous errors

I also fiddled with -K and -B parameters but was unable to get it to 
work.  It seems like this ought to be possible.  Any ideas?

address@hidden:/
 11 # tar --version
tar (GNU tar) 1.16.1
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software.  You may redistribute copies of it under the terms of
the GNU General Public License <http://www.gnu.org/licenses/gpl.html>.
There is NO WARRANTY, to the extent permitted by law.

Written by John Gilmore and Jay Fenlason.
address@hidden:/root
 12 #

-Sam