RE: iSCSI: underrun with a check condition

["Julian Satran" <satran@haifasphere.co.il>]

Santosh,

For any check condition in which the target did process the command this
is the expected behavior.
The example Eddy gave involves a target that due to ACA or BUSY does not
initiate processing the command.
In this case the target provider does not HAVE TO set the U/O bits (and
the associated values).
The relevant piece of information appears in SAM2 5.3.2 that indicates
that status precedence.
Obviously a target MAY set the U/O bits although  I doubt that an
initiator will look them up.

Regards,
Julo


-----Original Message-----
From: owner-ips@ece.cmu.edu [mailto:owner-ips@ece.cmu.edu] On Behalf Of
Santosh Rao
Sent: 16 February, 2003 23:28
To: Eddy Quicksall
Cc: "Ips@Ece.Cmu.Edu (ips@ece.cmu.edu)"
Subject: Re: iSCSI: underrun with a check condition


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