From: Santosh Rao <santoshr@cup.hp.com>
Message-Id: <200302162127.NAA08657@hpcuhe.cup.hp.com>
Subject: Re: iSCSI: underrun with a check condition
To: eddyq@ivivity.com (Eddy Quicksall)
Date: Sun, 16 Feb 2003 13:27:53 -0800 (PST)
Cc: ips@ece.cmu.edu ("Ips@Ece.Cmu.Edu (ips@ece.cmu.edu)")
In-Reply-To: <AEC4671C8179D61194DE0002B328BDD20D92@ATLOPS> from "Eddy Quicksall" at Feb 14, 2003 09:57:02 PM
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Eddy,

Yes, anytime the amount of data transferred does not match the data transfer
length specified, the target must set the U bit or O bit, depending on whether
an underflow or overflow occurred.

A recovered error check condition may be returned as the response to a scsi
command which was processed to completion. The recovered error indicates that a
previous command completed successfully with some recovery action by the device
server and the sense data provides additional details on that previous command.

The current command on which a recovered error check condition was returned may
have been processed to completion, or experienced some underflow or overflow.
This information must be conveyed by the target in the iscsi scsi response pdu
using the appropriate fields to describe the underflow or overflow.

Thanks,
Santosh


> Should the target set the U bit when it gives a check condition to a data-in
> command?
>  
>  
> Eddy