Fw: iSCSI: current UNH Plugfest

["Anshul Chadda" <anshul.chadda@trebia.com>]

My intent in making the MUST requirement is to make target send the sense
data along if it is setting the CHECK CONDITION in SCSI Response PDU (to
support and enable AutoSense).

 If we are making the iSCSI standard tight enough to make target "support
and enable AutoSense" (Clause 3.4.6, para 1 in draft 8), why not make a
requirement for target to send sense data if CHECK Condition is set (to make
fully tight).

 I am not even addressing situations that can happen on the initiator side.
Also, it is upto the initiator to handle a situation where SCSI Response PDU
has CHECK CONDITION set but no sense data with it. There are many reasons
why this can happen, one reason can be data digest error as you pointed out.
And the MUST requirement should not make the initiator assume things if the
SCSI Response PDU has the CHECK condition set.

 Regards,
Anshul

 ----- Original Message -----
 From: "Santosh Rao" <santoshr@cup.hp.com>
 To: <ips@ece.cmu.edu>
 Sent: Wednesday, October 31, 2001 4:41 PM
 Subject: Re: iSCSI: current UNH Plugfest


> > Robert Snively wrote:
 > >
 > > Sense Data will never be generated in a data segment to any command
 except
 > > REQUEST SENSE.  In that case, CHECK CONDITION will never
 > > be indicated unless the REQUEST SENSE command failed in
 > > some way, and (if autosensing is used), the CHECK CONDITION
 > > will be associated with its own set of sense information in
 > > the response PDU.
 >
 > The SCSI sense data is contained in the data segment of the SCSI
 > Response pdu. Hence, it is possible for the initiator to receive the
 > header of the scsi response pdu containing the SCSI Status, but not the
 > data segment (sense data) of the scsi response pdu, due to a data digest
 > error.
 >
 > - Santosh
 >
> > --
> > ##################################
> > Santosh Rao
> > Software Design Engineer,
> > HP-UX iSCSI Driver Team,
> > Hewlett Packard, Cupertino.
> > email : santoshr@cup.hp.com
> > Phone : 408-447-3751
> > ##################################
>