RE: iSCSI Autosense

[somesh_gupta@hp.com]

If we are looking for consensus on this issue, I agree with Ralph.
Better to clean up now than implement something that is waste of
energy.

Somesh

> -----Original Message-----
> From: ralphoweber@compuserve.com [mailto:ralphoweber@compuserve.com]
> Sent: Monday, August 28, 2000 8:03 PM
> To: ips@ece.cmu.edu
> Subject: FW: iSCSI Autosense
> 
> 
> Note: Clause numbers reference draft-satran-iscsi-01.txt.
> 
> There is nothing in the SCSI Architecture that requires the A
> Flags bit (byte 2 bit 7) described in 3.2 and 3.2.1.  Specifically,
> the SCSI Architecture does not require a transport to have the
> ability to disable Autosense.
> 
> Contingent Allegiance (the target state that follows a CHECK
> CONDITION in the absence of Autosense) is not a required SCSI
> behavior.  In fact, Contingent Allegiance is an out dated
> SCSI behavior that continues to be documented in SAM for
> backwards compatibility.  Contingent Allegiance is wholly
> superseded by the Autosense capability.
> 
> Autosense is dramatically simpler to implement provided the
> SCSI transport protocol allows for delivery of the sense data
> in the same packet as the CHECK CONDITION status (as is the
> case in iSCSI).
> 
> IMHO iSCSI would be well served by following the precedent
> set by FCP.  Remove the A bit and state explicitly that all
> iSCSI devices are required to support Autosense and that
> all instances of a CHECK CONDITION status shall be accompanied
> by Autosense data.
> 
> Note: These changes will also affect 3.3.7, 5.3 and possibly
> other clauses of the internet draft.
> 
> Thanks.
> 
> Ralph...
> 
> 
>