Re: iSCSI-related conclusions from Orlando interim Meeting

[julian_satran@il.ibm.com]

Santosh,

The answer is in the current draft.   AEN (newly renamed Asynch Messages)
can have an iSCSI origin or a SCSI origin.
SCSI can control only the SCSI reporting.  iSCSI initiators are supposed to
accept always iSCSI Asynch Messages. Well behaved targets are not supposed
to send SCSI messages when forbiden by SCSI.  The iSCSI initiator is not
mandated to check conformance to the above rule.

Julo

Santosh Rao <santoshr@cup.hp.com> on 20/01/2001 03:49:30

Please respond to Santosh Rao <santoshr@cup.hp.com>

To:   Black_David@emc.com, Julian Satran/Haifa/IBM@IBMIL
cc:   ips@ece.cmu.edu
Subject:  Re: iSCSI-related conclusions from Orlando interim Meeting




All,

I have raised this question on the reflector earlier without getting any
response.

If the target's only means for a logout is to "request a logout" through an
AEN
(now called Asynch Message) and host SCSI stacks disable AER by default
(which
is the behaviour today), then, targets DO NOT have a reliable means of
logging
initiators out, since they cannot send AE messages.

Targets MUST be allowed to send logouts or another reliable means be
defined in
the spec that allow targets to logout initiators. This peer-to-peer model
[wherein a target can originate logout] is not a violation of SAM and
allowing
targets to send logouts is the most expeditious form of error recovery at
the
target end.

Such a peer-to-peer model will also rid the spec of its convoluted way of
using
NOP-IN [which is a NOP response] as a NOP request when targets wish to
check
the  connection.

Targets MUST be allowed to originate Logout and NOP-OUT.

Regards,
Santosh

Black_David@emc.com wrote:

> - "AER" is used only for SCSI

> - iSCSI communication of asynchronous events is through a
> mechanism that is now called "Asynchronous Messages" - iSCSI
> uses these to implement AER

>  - If a SCSI initiator has disabled AER, iSCSI does not send
> the corresponding Asynchronous Messages

 - santoshr.vcf