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Date: Wed, 2 Jun 2004 06:35:02 -0700 (PDT)
From: Dan Strick <strick@covad.net>
Message-Id: <200406021335.i52DZ2eD034042@mist.nodomain>
To: dwmalone@maths.tcd.ie
cc: freebsd-scsi@freebsd.org
Subject: Re: 1TB issue
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On Wed, 2 Jun 2004 10:49:39 +0100, David Malone wrote:
>>
> I've heard from some people that there was a 2TB limit on SCSI
> devices, but it wasn't clear to me if this was a limit of the SCSI
> implementation they were using, or if it arose from the SCSI spec.
> What's actually the case here?
>>

The group 1 SCSI read/write command descriptor blocks have only
a 32 bit field for the device address (block number).

2^32 * 2^9 = 2^41

The group 4 SCSI read/write commands defined in the not-yet-published
SCSI Block Commands-2 (SBC-2) standard have a 64 bit field for the
device address.

Dan Strick