Re: iSCSI SCSI command F bit questions

["Julian Satran" <Julian_Satran@il.ibm.com>]

That is completely a SCSI issue. The
target may terminate any write at any point by status and report the data
it dit not write through residual lengths.

Julo

AClarke@attotech.com
Sent by: owner-ips@ece.cmu.edu

08/04/03 17:10

To	ips@ece.cmu.edu
cc
Subject	iSCSI SCSI command F bit questions

I have a few questions about iSCSI data transfer.

In section 10.3.1 of the spec describing the F bit, why is the word "may"
used?  I think that when Expected Data Transfer Length is larger than
DataSegmentLength the target "MUST" solicit the additional data.
 Is there
a situation when the target should not send an R2T for the rest of the
data?

Is it at the initiator's discretion to set this bit, even if InitialR2T=No,
ImmediateData=Yes, and DataSegmentLength is less than FirstBurstLength?


     10.3.1  Flags and Task Attributes (byte 1)

          The flags for a SCSI Command are:

          bit 0   (F) is set to 1 when no
unsolicited SCSI Data-Out PDUs
                follow this PDU.
 When F=1 for a write and if Expected Data
                Transfer Length
is larger than the DataSegmentLength, the
                target may solicit
additional data through R2T.


I would appreciate any comments or further explanation.

Aaron