FW: Target Reset handling

[Charles Monia <cmonia@NishanSystems.com>]

Abject apologies if this is a duplicate.  Since I never received a copy from
the ips mailing list or spotted the message in the ips archive, I figured
this may have been missent or lost in transit.

-----Original Message-----
From: Charles Monia 
Sent: Thursday, August 31, 2000 12:18 PM
To: Julian Satran (E-mail)
Cc: Ips (E-mail)
Subject: RE: Target Reset handling


A word to the wise:

There are a number of features in the SCSI Architecture that are not widely
supported by existing implementations. Asynchronous event notification and
auto-contingent allegiance are among them.

For that reason, relying on SCSI Asynchronous Event Notification, as
mentioned below, along with the auto-contingent-allegiance mechanism for
device synchronization discussed in another thread should be viewed with
caution.

As a design goal, at the level of the storage device abstraction, every
effort should be made to remain within the mainstream of features supported
by deployed SCSI implementations.

Charles

> -----Original Message-----
> From: julian_satran@il.ibm.com [mailto:julian_satran@il.ibm.com]
> Sent: Thursday, August 31, 2000 10:04 AM
> To: ips@ece.cmu.edu
> Subject: RE: Target Reset handling
> 
> 
> 
> 
> James,
> 
> The intent of the reset is radical - and assumes that something is bad
> at the target. Initiator May (or should?) be advised by AE on this
> happening.
> The TCP sessions are closed to eliminate any zombies (how 
> gracefully it is
> up to the
> implementer - but he should at least make sure that the AE gets to the
> initiators
> if he decides to signal it (although this might not be very useful).
> 
> And what you describe at 2 might happen but then some resources are
> overcomitted
> and that is an administrative issue.
> 
> I have the feeling that I am not understanding exactly the 
> scenario you are
> concerned
> with.  Are there initiators waiting to be connected before 
> the reset that
> can't get
> connected?   Are the host sockets over committed? In this 
> case you might
> want to have
> the iSCSI drivers have some pre-allocated ranges of sockets.
> 
> Regards,
> Julo
> 
<lots of stuff deleted>

Charles Monia
Senior Technology Consultant
Nishan Systems Corporation
email: cmonia@nishansystems.com
voice: (408) 519-3986
fax:   (408) 435-8385