Re: [Ips] iSCSI-specific unit attention conditions

Black_David@emc.com Mon, 30 March 2009 16:34 UTC

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Date: Mon, 30 Mar 2009 12:35:39 -0400
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Subject: Re: [Ips] iSCSI-specific unit attention conditions
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Paul,

> I am somewhat puzzled by the notion of T10 defining iSCSI things.
> Did these things receive any discussion on the IPS list?  If not,
> shouldn't that happen first?

Not to my knowledge, and (IMHO) yes.  The proposer of these ASC/Qs
to T10 appears to have dropped the ball in that regard.

In T10's defense, they do try to be accommodating, as there are SCSI
transport-related conditions and errors that can only realistically
be made visible as SCSI errors or unit attentions.  

> It seems to me that IPS should ask T10 for iSCSI related changes,
> not The other way around.  And nothing should be added without a
> description of how it is supposed to be used.

I agree that this is how it should work, but these ASC/Qs seem to
have slipped by and now need to be cleaned up one way or another.

FWIW, there's one more iSCSI-specific ASC/Q:

	47h 7Fh SOME COMMANDS CLEARED BY ISCSI PROTOCOL EVENT

This ASC/Q was added to deal with task side effects of some iSCSI
error handling; use of this ASC/Q is documented in Sections 6.5
and 10.14.5 of RFC 3720.

Thanks,
--David
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David L. Black, Distinguished Engineer
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