Tape dumping programs for Unix/Linux... - test-drb@ccmp.vtda.org

2 May 2002

...
  From: Raymond Moyers &lt;rmoyers(a)nop.org&gt;
 To: classiccmp(a)classiccmp.org
 Subject: Re: Tape dumping programs for Unix/Linux...
 Date: Thu, 2 May 2002 14:08:41 -0500
 In-Reply-To: &lt;20020502200530.E35218(a)MissSophie.unixag-kl.fh-kl.de&gt;

 On Thursday 02 May 2002 13:05, you wrote:
  On 2002.05.02 18:25 Raymond Moyers wrote:
   Whats wrong with cat ?  [...]
   I see most are using dd when cat is all they
need  cat(1) and dd(1) do not read / recognize the _physical_ block size of
 the tape. 
  At the portion of the work where you just want to get the stuff
  spooled to a file,  you dont care about "block size" yet, you
  just need to get it pulled off.

  Unix will treat any device as a stream of bytes

  On my old sony, mkboot is broken, you cant use the OS to
  create a bootable volume of itself

  so ... you hang the old scsi disk off your linux box and
  cat /dev/sdb  > /files/sonyhdimage.img

  hang the new scsi disk off your linux box

  cat files/sonyhdimage.img > /dev/sdb

  Put new disk in sony,  look mom  it boots !!

  Now you redo the disklabel and shove everything
  except root up to a new volume above the footprint of the old disk
  redo the middle volumes to suit ... move the stuff back down
  mount the new space as /usr/local whatever

  Now you have a 1g bootable disk in a machine that cannot create
  one for itself...

  Do you see what im getting at here ?   hello ?

  and guess what ... i never even bother to involve myself with
  any "block sizes"    even as the multiple volumes on
  that image uses a mix of logical block sizes. 
Guess what.  You aren't dealing with structured magtapes.  And it's
a very rare disk drive that has a mixture of block sizes.

    carl
-- 
        carl lowenstein   marine physical lab   u.c. san diego
                                          clowenstein(a)ucsd.edu