Persistent Reservation question

Elliott, Robert (Server Storage) Elliott at
Fri Jun 13 18:10:47 PDT 2003

* From the T10 Reflector (t10 at, posted by:
* "Elliott, Robert (Server Storage)" <Elliott at>

> -----Original Message-----
> From: Ken Craig [mailto:kcraig at] 
> Sent: Thursday, June 12, 2003 1:08 PM
> To: t10 at
> Subject: Persistent Reservation question
> I have a question concerning Section 6.12.3,
> PERSISTENT RESERVE OUT parameter list, in
> revision 13 of SPC-3.  There are three
> paragraphs that explain the meaning and usage
> of the SPEC_I_PT, ALL_TG_PT, APTPL bits in
> the parameter list.  The paragraphs for the
> ALL_TG_PT and APTPL bits make specific mention
> of the fact that the bits are to be ignored
> for any Service Action but the two listed.
> However there is no statement to the same
> effect in the paragraph that describes the
> SPEC_I_PT bit.  Is this an oversight or is
> the setting of the bit considered to be
> valid for all PERSISTENT RESERVE OUT Service
> Actions?

There are two paragraphs that discuss SPEC_I_PT.

The first is really the PARAMETER DATA LENGTH paragraph, noting that the
length must be 24 if SPEC_I_PT is 0.

The second, above table 107, is the main SPEC_I_PT paragraph.  It does
mention that the additional parameter data, if present, is ignored
(rather than saying the SPEC_I_PT bit is ignored).

All three bits are mentioned in Table 108 (part 2), which marks them
valid/ignored for the same service actions.

> Also, if the SPEC_I_PT or ALL_TG_PT bits are
> set for the appropriate Service Actions but
> the Target does not support the option should
> the Target return the same error information
> as it does for the APTPL bit being incorrectly
> set?

If the logical unit was based on SPC-2, INVALID FIELD IN PARAMETER LIST
would be returned by logical units that check reserved fields.  Nothing
would be reported by logical units that do not check reserved fields.
If designed with SPC-3 knowledge, it is supposed to return INVALID FIELD
IN PARAMETER LIST.  The APTPL bit has always been defined, so it's safe
to require it be checked in all versions of SPC-n.

> Thanks,
> Kenneth Ray Craig, Jr.

Rob Elliott, elliott at
Hewlett-Packard Industry Standard Server Storage Advanced Technology

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