[Ips] iSCSI-specific unit attention conditions

Black_David@emc.com Mon, 30 March 2009 14:24 UTC

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Here's another piece of "housekeeping" for the new STORM WG-to-be
- I've been informed by a knowledgeable T10 participant that:

> T10 proposal 05-406 (from Bill Galloway, Pivot3) added 3
> iSCSI-specific unit attention condition additional sense codes
> in SPC-4:
> 	- 3Fh/12h iSCSI IP ADDRESS ADDED
> 	- 3Fh/13h iSCSI IP ADDRESS REMOVED
> 	- 3Fh/14h iSCSI IP ADDRESS CHANGED
> 
> r0 used a more generic "DEVICE PORT ADDRESS" phrase, but r1
> changed that to "iSCSI IP ADDRESS" upon recommendation by the
> [T10] CAP WG.
> 
> However, there is no mention in any standard of when these are
> used (unlike all the other unit attention conditions, whose causes
> are clearly defined).  With the accepted names, that belongs in
> iSCSI itself.
 
FWIW, these ASC/Q value pairs appear to have been added to SPC-4
without any cross-checking with the IETF, which would serve to
explain why there is no documentation anywhere about when or how
to use them.  Since these ASC/Qs are iSCSI-specific, that task
falls to the iSCSI specification(s), unless these ASC/Qs are
removed or have their names changed to no longer be iSCSI-specific.

Hence: 
- the "new features" STORM draft should explain how to use these
	ASC/Qs
--- AND/OR ---
- discussion here and in the to-be-formed storm WG should generate
	a proposal to T10 about what should change and why.

If these ASC/Q pairs remain and remain iSCSI-specific, they may be
the first feature beyond SAM-4 that goes into the "new features"
STORM draft.

This situation was originally pointed out to me about a year ago,
and there was some private discussion at that time.  This is an
opportunity for the participants in that discussion to express
their views on what should be done and why (as we now have a vehicle
to document their use with iSCSI *if* we choose to do so). 

FYI,
--David
----------------------------------------------------
David L. Black, Distinguished Engineer
EMC Corporation, 176 South St., Hopkinton, MA  01748
+1 (508) 293-7953             FAX: +1 (508) 293-7786
black_david@emc.com        Mobile: +1 (978) 394-7754
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