Subject: Re: more fsck troubles
To: Taras Ivanenko <>
From: David Brownlee <>
List: port-mac68k
Date: 07/30/1996 18:04:04
	You should be able to 'zero out' the drive by running
	'dd if=/dev/zero of=/dev/rsdXc' (Where X is your drive number,
	be careful you dont give the wrong drive ! :)

                   David/abs             (

.---- I've been too drunk to love ----.--- I've been too drunk to remember -.
|          Too drunk to care          |     The hell of the night before    |
|  Looked like death, felt like Hell  |    I've been drinking myself blind  |
`------ Been the worse for wear ------'--- And still I'll drink some more --'

On Tue, 30 Jul 1996, Taras Ivanenko wrote:

> I saw the same problem with fsck (BAD SUPERBLOCK ...) on my
> IIcx+Conner1Gb external drive. I looked at the source code and saw, if I
> remember correctly, that fsck tries to read the last copy of superblock
> from a strange place, get zero block (the drive was brand new) and
> then did calculation by zero division. At the end I took the geometry
> information from NetBSD tools (newfs -n) and typed it into MacOS
> utility. I had also to adjust the partition sizes to be the exact
> multiple of cylinder groups. So I think this is the disk geometry
> problem. Somehow MacOS utility calculates disk geometry from the whole
> disk and Unix utils take into account only partition size. If the disk
> has variable number of sectors/cylinder you got the problem. I can not
> test those assumptions or repeat the problem without new disk.
> 	Taras Ivanenko.