T10/97-264r0 -- SCSI Enclosure Profile TR Project Proposal
ROWEBER at acm.org
ROWEBER at acm.org
Fri Oct 31 19:10:27 PST 1997
* From the T10 (formerly SCSI) Reflector (t10 at symbios.com), posted by:
* ROWEBER at acm.org
For a New
NCITS Technical Report
SCSI Enclosure Profile
November 6, 1997
1. IDENTIFICATION OF PROPOSED PROJECT
1.1 TITLE: SCSI Enclosure Profile.
1.2 PROPOSER: T10.
1.3 DATE SUBMITTED: November 6, 1997
1.4 PROJECT TYPE: DT - Development of a technical report within an NCITS
2. JUSTIFICATION OF PROPOSED TECHNICAL REPORT
With the near completion of SES (SCSI Enclosure Services) and SCC-2 (SCSI
Controller Commands -2) standards, product developers need guidance for
cost-effective engineering of RAID (Redundant Arrays of Independent Disks)
products based on these new standards. It is important that both host
software and RAID controller firmware be developed at minimum time and cost
so that initial industry acceptance of these new standards can be achieved.
A usage profile describing a minimum usage definition based on the
standards and agreed to using the NCITS consensus process is proposed to
meet these needs.
2.2 RECOMMENDED SCOPE OF TECHNICAL REPORT:
Candidates for inclusion in the Enclosure Profile technical report are:
a) Device model concepts for RAID subsystems using SCC-2 and SES;
b) Lists of recommended options from SES, SCC-2, SPC-2 (SCSI Primary
Commands -2), and SBC (SCSI-3 Block Commands);
c) Recommendations for device discovery procedures, including but not
limited to: world-wide name usage, controller discovery (initial and
after hot swaps), volume set discovery (initial and after hot
swaps), and usage of the Report LUNs command;
d) Usage of the LUN_Z, including but not limited to: basic principles,
reservations, and LUN_Z embedded in a volume set LUN;
e) Recommendations for usage of SCC-2 volume set configuration
f) Recommendations for usage of SCC-2 and SES commands for volume set
g) Recommendations for usage of SCC-2 and SES commands for RAID
h) Recommendations for usage of SCC-2 and SES commands for RAID
i) Recommendations for usage of SES commands for management and
monitoring of the enclosure or enclosures associated with one or
more RAID controllers;
j) Relationships between SCSI transport protocol layers and RAID
controllers, if any; and
k) Other concepts or recommendations that address the needs described
above that may be identified by participants during the development
of the technical report.
2.3 EXISTING PRACTICE IN AREA OF PROPOSED TECHNICAL REPORT:
Current industry practice relies on vendor-specific firmware, software, and
interchange protocols to manage RAID products. The proposed technical
report will describe a minimally equivalent capability based on the SES and
SCC-2 standards, thus promoting the use of those standards.
2.4 EXPECTED STABILITY OF PROPOSED TECHNICAL REPORT WITH RESPECT TO CURRENT
AND POTENTIAL TECHNOLOGICAL ADVANCE:
The nature of the proposed project is to promote and enhance compatibility
among RAID hardware and software products from different vendors. This
should insure greater future interoperability and stability in the face of
3. DESCRIPTION OF PROPOSED PROJECT:
3.1 TYPE OF DOCUMENT: Technical Report.
3.2 DEFINITION OF CONCEPTS AND SPECIAL TERMS:
LUN_Z - The name SCC-2 gives to the LUN within an array controller
device to which an application client directs commands that manage
volume sets, component devices, and other constituents of a storage
RAID - (Redundant Array of Independent Disks) a collection of disk
drives managed by a controller (or equivalent device) such that several
disks appear to applications programs as a single disk. In most cases,
the several disks are managed in ways that improve either performance
or data availability or both.
3.3 EXPECTED RELATIONSHIP WITH APPROVED NCITS REFERENCE MODELS:
The SCSI Enclosure Profile technical report is intended for use in closed
3.4 RECOMMENDED PROGRAM OF WORK:
The following program of work is planned for the SCSI Enclosure Profile
1) Solicit continuing participation by the current membership of T10
through NCITS procedures. Invite comments and proposals from
organizations that may have a contribution to the SCSI Enclosure
Profile technical report.
2) Prepare a draft technical report based on proposals submitted and
other information gathered during the initial investigation.
3) Consider the results of SCSI Enclosure Profile testing as may be
available to the committee through the voluntary efforts of the T10
4) Submit the draft technical report to NCITS for further processing.
3.5 RESOURCES - INDIVIDUALS AND ORGANIZATIONS COMPETENT IN THE SUBJECT
The current membership of T10 includes representatives from all parts of
the computer industry, from semiconductor chip manufacturers to large
mainframe system manufacturers. When appropriate, government agencies have
participated in T10 activities in the past and can be expected to do so in
the future. The current members of T10 have expressed their desire to
participate and cooperate in the development of this proposed technical
There are sufficient resources to complete the development of this
technical report without delaying work on other projects.
3.6 RECOMMENDED NCITS DEVELOPMENT TECHNICAL COMMITTEE:
It is recommended that the development work be done in Technical Committee
T10 which is responsible for developing the family of SCSI standards.
3.7 ANTICIPATED FREQUENCY AND DURATION OF MEETINGS:
Technical Committee T10 meets bimonthly, except January. Specific task ad
hoc groups are called as may be required for one to three days between the
regular meetings but their results are not binding.
3.8 TARGET DATE FOR DRAFT TR TO NCITS: May 1999.
3.9 ESTIMATED USEFUL LIFE OF TECHNICAL REPORT:
It is anticipated that this technical report will have a useful life of 5
4. IMPLEMENTATION IMPACTS
4.1 IMPACT ON EXISTING USER PRACTICES AND INVESTMENTS:
The proposed SCSI Enclosure Profile technical report will provide
guidelines for typical RAID subsystems, which should facilitate an
evolutionary growth away from costly and inefficient vendor-specific
product implementations. Since the recommendations in the proposed
technical report are in no way binding, the impact on existing user
practices and investments is limited to whatever impact the product
development community decides to allow.
4.2 IMPACT ON SUPPLIER PRODUCTS AND SUPPORT:
4.3 TECHNIQUES AND COSTS FOR COMPLIANCE VERIFICATION:
4.4 LEGAL CONSIDERATIONS:
There are no known legal considerations. A Call for Patents will be made.
5. CLOSELY RELATED STANDARDS ACTIVITIES
5.1 EXISTING STANDARDS:
BSR Number Title
ANSI X3.270-1996 SCSI-3 Architecture Model
ANSI X3-301-1997 SCSI-3 Primary Commands
ANSI X3.276-1997 SCSI-3 Controller Commands
ANSI X3.292-1997 SCSI-3 Interlocked Protocol
ANSI X3.269-1996 SCSI-3 Fibre Channel Protocol
ANSI X3.294-1996 Serial Storage Architecture SCSI-2 Protocol
5.2 NCITS STANDARDS DEVELOPMENT PROJECTS:
BSR Number Title Project
SCSI Architecture Model - 2 T10/1157-D
SCSI Primary Commands - 2 T10/1236-D
SCSI Controller Commands - 2 T10/1225-D
ANSI NCITS.305-199x SCSI Enclosure Services T10/1212-D
ANSI NCITS.306-199x SCSI-3 Block Commands T10/0996-D
ANSI NCITS.309-199x Serial Storage Architecture T10/1051-D
Serial Bus Protocol - 2 T10/1155-D
SCSI-3 Fibre Channel T10/1144-D
Protocol - 2
ANSI X3.302-199x SCSI-3 Parallel Interface - 2 T10/1142-D
5.3 NCITS STUDY GROUPS: None.
5.4 OTHER RELATED DOMESTIC STANDARDS EFFORTS: None.
5.5 ISO/IEC JTC 1 STANDARDS DEVELOPMENT PROJECTS: All standards listed in
5.1 and 5.2 have been or are being processed as a NWI at JTC1/SC25/WG4..
5.6 OTHER RELATED INTERNATIONAL STANDARDS DEVELOPMENT PROJECTS: None.
5.7 RECOMMENDATIONS FOR COORDINATING LIAISON: The RAID Advisory Board
should be notified of the completion of key milestones in development of
this technical report.
5.8 RECOMMENDATIONS FOR CLOSE LIAISON: None.
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