RE: draft-ietf-ips-scsi-mib-04 comments

["Elliott, Robert (Server Storage)" <Elliott@hp.com>]

That's a separate Identifier (which is currently optional in SCSI), which would be returned as its own ScsiLuIdentifier object.

I agree the logical unit could return one target port name and a matching relative port identifier to return a consistent set; however, how should it choose which port?

Ideally, the logical unit should be able to:
a) return all the target port names
b) return all the relative target port identifiers
c) relate the target port name/relative target port identifiers to the ScsiTgtPort objects

I think this is best left to a future version of the MIB rather than addressed now, since T10 is still enhancing the VPD structures (target device names are being added).  This version can just not return any port-specific identifiers.

--
Rob Elliott, elliott@hp.com
Hewlett-Packard Industry Standard Server Storage Advanced Technology
https://ecardfile.com/id/RobElliott




> -----Original Message-----
> From: Narsimha Reddy CH [mailto:creddy@npd.hcltech.com] 
> Sent: Tuesday, December 10, 2002 9:30 AM
> To: Elliott, Robert (Server Storage)
> Cc: ips@ece.cmu.edu; michele@sanrad.com; black_david@emc.com; 
> erodrigu@Brocade.COM
> Subject: Re: draft-ietf-ips-scsi-mib-04 comments
> 
> 
> Hi Robert,
> 
> 	This is regarding the technical comment given by you 
> with respect to devices having 
> multiple ports. In this case my opinion is that it is 
> possible to know the target port identifier ( relative port 
> identifier according to SPC-2 ) to access the Logical Unit.
> 
> Please refer  Table 174 and Table 175 under the section 
> section 8.4.4 Device identification page. Since, if the 
> ASSOCIATION value is 1h, the IDENTIFIER value contains a 
> four-byte binary number identifying the port relative to 
> other ports in the device according to the following (Table 
> 175) values.
>                 ^^^^
> 
> 
> Table 175  Relative port identifier values
> --------------------------------------------
> 0h                            Reserved
> 1h                            Relative port 1, historically 
> known as port A
> 2h                            Relative port 2, historically 
> known as port B
> 3h-7FFFFFFFh                  Relative port 3 through 2 147 483 647
> 80000000h-FFFFFFFFh           Reserved
> 
>  In this case, the CODE SET field shall be set to 1h and the 
> IDENTIFIER LENGTH field shall be set to 4. If the ASSOCIATION 
> value is not 1h, use of this identifier type is reserved.
> 
>  So we can keep the value 1 (hex) for scsiLuIdAssociation 
> field in the population example for 
> parallel scsi.
> 
> 
> Thanks,
> -Narsimha
> 
> 
> "Elliott, Robert (Server Storage)" wrote:
> > 
> > Comments on draft-ietf-ips-scsi-mib-04:
> > 
> > Technical:
> > =========
> > COMMENT: For a logical unit in a multiple ported device, the 
> > ScsiLuIdentifier cannot return a scsiLuIdAssociation of type "port" 
> > (01 binary) because the target port being used to access 
> the logical 
> > unit is not known.  (The MIB is probably being retrieved through a 
> > non-SCSI channel... which target port does the logical unit pick?)
> > 
> > For this version of the MIB, I'd just require that 
> scsiLuIdAssociation 
> > be set to 0 (or possibly 2) and figure out how to report 
> target-port 
> > specific information in the future.
> > 
> > This occurs in the ScsiIdAssociation textual-convention and 
> in the parallel SCSI example:
> > "   ScsiIdAssociation ::= TEXTUAL-CONVENTION
> >      STATUS    current
> >      DESCRIPTION
> >           "This Textual Convention specifies what the identifier is
> >           associated with (e.g, with the addressed physical/logical
> >           device or with a particular port) for the 
> identifier contained
> >           in an Identification Descriptor returned in a 
> Logical Unit's
> >           Device Identification Page, and is formatted as 
> defined in T10
> >           SPC-2 (see REFERENCE) table 178 û Association."  "
> > and:
> > "   11.14 scsiLuIdentifer:
> > 
> >       Attribute                       Value
> >       ----------                      ------
> >       scsiInstIndex                   1
> >       scsiDeviceIndex                 2
> >       scsiLuIndex                     1
> >       scsiLuIdIndex                   1
> >       scsiLuIdCodeSet *1              2
> >       scsiLuIdAssociation *2          1
> >       scsiLuIdType *3                 1
> >       scsiLuIdValue                   IETFsl318203-0004
> > 
> >      *1 - The identifier field will have ASCII graphic codes.
> >      *2 - The identifier is associated with the port that 
> received the
> >      request. "
> > 
> > Change the example value to 0 and remove note 2.
> > 
> > Also note that SPC-3 is changing 0 to mean "logical unit" 
> rather than 
> > "physical/logical device" and 1 to mean "target port".  It is also 
> > adding 2 as "target device" (which could be reported through this 
> > MIB).
> > 
> 
> -- 
> 
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