Subject: Re: largest disk in a vs4000/90
To: None <,>
From: Carl Lowenstein <>
List: port-vax
Date: 07/26/2003 21:00:24
> Date: Sat, 26 Jul 2003 11:39:56 -0400
> From: John Wilson <>
> To:
> Subject: Re: largest disk in a vs4000/90
> From: "Antonio Carlini" <>
> >Having never formatted a SCSI disk in all my life, I guess
> >I must be missing something! Why do you format them?
> People already talked about reviving slightly munged disks.  Also,
> if a disk has personal stuff on it you may want to reformat it before
> giving it away, just as an easy way to be sure every sector is overwritten.
> Finally ... maybe I'm the only one who still thinks removable disks are cool,
> but I use magneto-opticals all the time (Fuji Dynamos).  And those may or
> may not come with the low-level format already done, anyway I always reformat
> them (using my PDP-11 emulator, just for fun because it can).

Is there some confusion here betwen "format" which uses the disk
firmware to rewrite the sector headers, and "surface check" which
can overwrite all the existing data?  These are certainly different
functions in some Unix-based "format" programs.

> Re not being able to format due to 8 GB firmware limit -- I would think the
> firmware would just use the SCSI "FORMAT UNIT" command, in which case it
> doesn't matter how big the firmware thinks the disk is.  But I wouldn't
> know for sure, anyway I doubt it hurts to try.
> Yes I know everyone hates PCs but:  the BIOS setup on most PC SCSI cards has
> commands to do low-level formatting of SCSI drives.  You just have to type
> the right stupid key combination at the right instant during the self-test...

Also the SCSI BIOS has commands to do surface check.  You don't have
to do both.

    carl lowenstein         marine physical lab     u.c. san diego