Re: Repairing corrupted IIgs hardisk?

["Michael J. Mahon" <mjmahon@aol.com>]

Mitchell Spector wrote:
> "Michael J. Mahon" <mjmahon@aol.com> wrote:
>
>
> > A2Pro wrote:
> >
> > > Hi!
> > >
> > > Mitchell Spector wrote:
> > > <--- snip --->
> > >
> > > >   Is there any other software worth trying, perhaps something
> > > > like Universe Master?
> > >
> > > <--- snip --->
> > >
> > >    I was going to suggest Glen Bredon's "MR.FIXIT" but it probably
> > > won't be any help if the partition map is a mess as "MR.FIXIT" works
> > > on partitions.  But it wouldn't hurt to try as long as you stay with
> > > the 'test' option.
> >
> > I agree that it sounds like the partition table is damaged.
> >
> > If you could just re-write the partition table, you might find
> > your disk intact...
>
>
>     I tried Universe Master, Deliverance and Mr. Fixit, all proved
> futile since they will only work on partitions you can *SEE*. If 
> for the partition is not visible to ProDOS, it's not visible to these
> repair utilities. ProSel-16's volume repair option proved equally 
> as useless. Rather distrubing, I though they were more robust.
>
>     In the end I just gave up and re-partitioned and formatted
> the drive, restoring from a 6 month old backup off Zip disks.
> Not sure where the fault lies--SCSI devices improperly set up,
> damaged internal SCSI cable, ZipGS instability, or even a faulty 
> motherboard. Whatever the case may be, even though I lost 
> only a small amount data this time, it still leaves me with little
> confidence in storing data on the GS.
>
>     I really need to take the whole thing apart and get it stable
> again, I think a new ROM 3 motherboard is a good place to
> start. Coming up on 20 years I've owned my GS, not about to 
> give up on it yet. :)

Right.

You can't use any tools that work "on" partitions to work on
the partition map, since the partition map is only accessible
as raw disk sectors.

Programs that can partition disks access them as raw disks,
and would be a good starting point for a partition map repair
program.

In the case you had, I think I would have tried simply re-partitioning
the disk *exactly* as it had been partitioned originally.  Odds are
good that the partitions would then be accessible, at least for the
purpose of creating a current backup.

Then I would have proceded just as you did, but restoring from the
new backup, then checking all partitions for correct data structures.

Hopefully, recovery of the last six months worth is not too onerous...

-michael

NadaPong: Network game demo for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

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