Re:
> We have started having 2 different disk errors on one of our disk
> drives.  Luckily this machine is no longer a production machine because a
...
> year.  Is it possible to store just the faulty disk, replace it and
> restore? All the disks are members of the system volume set.

No.

It is possible, however, to avoid the install.
You can clone the data from the flaky disk onto a new good disk.

There are two basic methods, each with pros/cons:

   1) offline

   2) online


1) offline clone

Your CE should be able to do:

   1) connect a new drive (preferably identical to the flaky drive,
      or at least as large as it)

   2) boot to the ISL prompt

   3) run a tool to copy the flaky disk to the new disk

   4) disconnect the flaky drive

   5) change the ID/cabling on the new drive to match the old drive's ID/cabling

   6) boot into MPE.


NOTE: I don't recall the name of the offline tool (but it doesn't seem to be
one of: DISCUTIL, ODE/COPYUTIL (only seems to do disk->tape and tape->disk))


2) online clone

<plug>
De-Frag/X, from Lund Performance Solutions (www.lund.com), has a
CLONEDISK command.

The way you would use it is:

   1) connect an identical (preferably, otherwise an "at least as large") disk
      drive to your HP 3000 and configure it in as a new ldev.
      Don't do anything to it with VOLUTIL.

      Let's assume the flaky drive is ldev 2, and the newly added drive is
      ldev 40.

   2) reboot with "start norecovery nosysstart"
      (We want as idle a system as possible)
      logon as MANAGER.SYS.
      :limit 0,0

   3) :defragx
      clonedisk 2 to 40


   4) upon termination of the CLONE, TURN OFF THE SYSTEM POWER!

      Do *NOT* do a =SHUTDOWN.
      Do *NOT* do *ANYTHING* other than immediately powering off the system.

      Why?  You don't want MPE changing data on the flaky disk after it's been
      copied to the new disk!  This is *important*.
      (That's also why we tried to get as idle a system as possible)

   5) disconnect the flaky disk.

   6) If the new disk is on the same SCSI (or HP-IB) channel as the
      flaky disk, then change the ID (SCSI or HP-IB) on the new disk
      to match what the old disk was (so it appears as the old ldev, not
      that that's very important for anything other than ldev 1)

   7) bootup

Caveat: There's a chance that the some of the data on the new disk was "stale",
because MPE changed something vital on the flaky disk (and on other disks!)
after you copied that section of the flaky disk.  If that happens, and if the
data was really important, you may still have to do an install.

Pros: you don't need an HP CE for this approach.
Cons: you need De-Frag/X.  (Hey, that's a pro for me :)

Experience: I've only done this once (it worked), and I've only heard of a
handful of people doing it ... all successful.  Still...
</plug>


NOTE: either "clone" method suffers from the same problem: you might have
bad data copied from the flaky disk to the new disk.  But, if you don't have
an *accurate* backup, there may be no better choice.  (I.e., you don't know how
long the drive's been flaky.)

Stan Sieler                                           [log in to unmask]
www.allegro.com/sieler/wanted/index.html          www.allegro.com/sieler