Update of SFF-8067 enclosure services on 40-pin SCA FC drive

[Bob Snively]

* From the SCSI Reflector (scsi at symbios.com), posted by:
* bob.snively at Eng.Sun.COM (Bob Snively)
*

A new copy of SFF-8067 is being sent out on the SFF reflector including the
responses to the questions below.


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Bob Snively				         Phone:	   (415) 786-6694
Sun Microsystems Computer Company	         FAX:	   (415) 568-9603
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>From Gene_Milligan at notes.seagate.com Tue Jan 21 21:42:02 1997
>Date: 21 Jan 97 23:38:54 
>Subject: Re: Update of SFF-8067 enclosure services on 40-pin SCA FC drive
>
>
>It is not clear what the freestanding Reference of SCSI-3 points to.
>

Got it.

>>The pull-up resistor shall be on the backplane and shall have a value 
>appropriate to limit the 
>>required assertion drive to less than the specified Iol.  The resistance
>>should not be less than 3 k ohms.
>
>What is "lol"?

Little old lady.  Loss of Light.  However, Iol is "Current, output, low"

>
>>The device may be removable from the enclosure through an external port or may 
>be >permanently installed in the enclosure. 
>
> For a FC device, this is an unfortunate use of the term port.
>

True.  How about "access door"?

>> After successfully identifying the enclosure as supporting
>>the SFF-8067 Enclosure Services protocol, the device performs a Command
>>phase (using a fixed number of Write phase transfers) that provides 
>>the identification of the page to be transfered and
>>the direction of the transfer. 
>
> There should be a description of the requirements if the identification shows 
>that the enclosure does not support the protocol.
>

The proper behavior is pretty well documented in section 6.4.2.1, where
the discovery process tells you what to do for each different failure to
identify an enclosure services processor.

>> post TBD
>
> What is happening to define TBD?

It had been selected some time ago.  The figure is modified to indicate that
the value is 35.

>
>>The enclosure services device model is defined in SCSI-3 Enclosure 
>>Services command set (SES),  X3T10/Project 1212, revision 8.  
>
> I hope it is not necessary to tie this to an intermediate revision.
>

The references list and this paragraph are fixed to allow revision 8a or
above.

>>The device model allows commands accessing enclosure
>>services information to be executed to any device.  
>
> Should this be "to be sent to any device" or "to be executed in any device"?
>

I replaced the culprit with:

  The device model allows commands accessing enclosure services 
  information to be sent to any type of device.   

>There is some danger in repeating SES requirements since one or the other of 
>the documents could in the future independantly change a requirement.
>

This is true.  To correct this, I have placed the following paragraph
in section 7.0, along with informative/normative labels in the titles
of the appropriate sections:

  This section provides an overview of the proper mapping between 
  the enclosure services commands defined by the SCSI-3 Enclosure Services
  command set (SES) and the enclosure services interface defined by this 
  document.  Section 7.1, describing the SCSI command definitions, is 
  informative. Future revisions to the SES may modify the functions and formats
  communicated across the SCSI interface.  The ESI interface functions
  defined in sections 7.2 and the mechanisms relating the ESI and
  SCSI interfaces defined in sections 7.3 and 7.4 are normative.  Section
  7.5 describing the ASC/ASCQs for such devices is informative.

>>It is not an error if a RECEIVE DIAGNOSTIC RESULTS command is executed 
>>with an Allocation Lenth different than the Page Length + 4.
>
> I think this should be "It is not an error for a RECEIVE DIAGNOSTIC RESULTS 
>command to have an Allocation Length less than the Page Length + 4."
>

Shouldn't the allocation length be allowed to be both shorter and longer?
In particular, it would seem to me that a long allocation length would
be arbitrarily selected when the first attempt is made to read the
configuration page.
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