RE: iSCSI : Aborting non-SCSI tasks.

["Douglas Otis" <dotis@sanlight.net>]

Santosh,

Should the Service Delivery Subsystem (iSCSI) be responding to Task
Management requests?  Unless you wish to burden the transport with the
prospect of sorting and tracking LUN:TAG values, the transport should not
attempt to interpret SCSI commands.  There should be a simple scheme for
handling these situations without having the transport take on the
characteristics of a SCSI target.  Philosophically, this does not isolate
the functions in a layered manner.  It gets complex very quickly otherwise.

Doug



> Hi Charles,
>
> non-scsi tasks refers to Login, Logout, Text & NOP-OUT PDUs.
>
> Initiators will need to time these tasks [exchanges ?] and how do they
> deal with a timeout of such non-scsi tasks [exchanges/PDUs/commands] ?
>
>
> Regards,
> Santosh
>
>
> Charles Monia wrote:
> >
> > Hi Santosh:
> >
> > > The iSCSI spec is missing description on how non-SCSI tasks should be
> > > aborted
> >
> > What is a non-SCSI task?
> >
> > Charles
> > > -----Original Message-----
> > > From: Santosh Rao [mailto:santoshr@cup.hp.com]
> > > Sent: Tuesday, April 24, 2001 10:27 AM
> > > To: IPS Reflector
> > > Subject: iSCSI : Aborting non-SCSI tasks.
> > >
> > >
> > > All,
> > >
> > > The iSCSI spec is missing description on how non-SCSI tasks should be
> > > aborted in order to flush stale PDUs of that task. Initiators will
> > > typically time non-SCSI [& SCSI] tasks and will need to resort to some
> > > form of abort and cleanup action on a timeout of the non-scsi task.
> > >
> > > This is required in order to safely re-use the task tag resources
> > > without the danger of stale PDUs arriving from a previous
> > > incarnation of
> > > that task tag.
> > >
> > > The spec should provide some description on how this is to be done.
> > > Perhaps, the semantics of Abort Task can be extended to non-SCSI tasks
> > > as well, to avoid defining a second abort mechanism for
> > > non-SCSI tasks.
> > >
> > > - Santosh
> > >