[comp.sys.apollo] BAD EXTERNAL DISK - HELP

scalera@batpa15.bnr.ca (Eric Scalera) (12/18/90)

I have been unsuccessful in trying to mount an external drive to a DN4500.
This drive stores all the products located in my authorized area.  Apollo
is telling me my disk might be forever hosed.


Errors:

  When trying to mtvol I get the message cannot mtvol ecc error in sector id field.

  I ran lsyserr and got a whole page of disk errors for Phys daddr = 1: ecc error 
  in sector id field.  I also ran disk_err and recieved info on the 1k block with 
  the error.  Apparently the 1k block is at daddr 1 which is were sysboot is kept
  This is not being uses as a bootable disk, but I'm sure the VTOC manager uses
  this block when mounting the disk.  

I really would like to slvage this disk.  It has a lot of vital info on it that
has not been responsibly backed up.



 
-- 
Rick Scalera

#include <disclaimer.h>
"BNR does not share my opinions. I wouldn't be an MSS if it did"

rees@pisa.ifs.umich.edu (Jim Rees) (12/19/90)

In article <1990Dec18.142147.3778@bnr.ca>, scalera@batpa15.bnr.ca (Eric Scalera) writes:

  I have been unsuccessful in trying to mount an external drive to a DN4500.
  This drive stores all the products located in my authorized area.  Apollo
  is telling me my disk might be forever hosed.
..
    When trying to mtvol I get the message cannot mtvol ecc error in sector id field.
    I ran lsyserr and got a whole page of disk errors for Phys daddr = 1: ecc error 
    in sector id field.  I also ran disk_err and recieved info on the 1k block with 
    the error.  Apparently the 1k block is at daddr 1 which is were sysboot is kept
    This is not being uses as a bootable disk, but I'm sure the VTOC manager uses
    this block when mounting the disk.

Daddr 0 is the physical volume label.  Daddr 1 is the logical volume label
for volume 1.  After that is sysboot, followed by volume 1.

If daddr 1 is the only one that's been corrupted, you're in luck, since
there are spares for the lvol labels.  An ecc error in the sector id field
means the format has been corrupted, so the first thing to do is reformat. 
Do not use invol for this!  Instead use /systest/ssr_util/fixvol.  Tell it
to reformat track 0.  It will try to read the track first and save any data
it can.  Then tell it to "fix pv" and "fix lv."  Then try salvol -av to see
if you have any other bad blocks.  If this doesn't do it, go back to fixvol,
ask for help, and play around.  But be careful!  You can really hose
yourself with fixvol if you want to.