Minutes of SSC/SMC Working Group Mtg, 12-Sep-96 Natik, MA

Erich Oetting erich_oetting at stortek.com
Thu Sep 12 15:27:35 PDT 1996

* From the SCSI Reflector (scsi at symbios.com), posted by:
* erich_oetting at stortek.com (Erich Oetting)
Accredited Standards Committee                  Doc. Number X3T10/96-244r0
X3, Information Technology

To:       Membership of X3T10

From:     Erich Oetting

Subject:  Minutes of SSC/SMC Working Group Meeting
                 Natik, MA, Sept. 12, 1996


1. Opening Remarks

2. Approval of Agenda

3. Attendance and Membership

4. SMC Topics
4.1 Reserve Element(6) & Release Element(6)
4.2 World Wide IDs

5. SSC Topics
5.1 Tape on Serial Interfaces
5.2  More than 256 Partitions
5.3 Error Recovery for Tapes on Serial Interfaces.

6.   Other Topics

7.    Meeting Schedule
8.    Adjournment

                              Results of Meeting

1.    Opening Remarks

Erich Oetting, the SMC Technical Editor, called the meeting to order at
9:00 a.m., Thursday, Sep 12, 1996.  He thanked Charles Monia of Digital for
arranging and hosting the meeting.

As is customary, the people attending introduced themselves and a copy of
the attendance list was circulated.

The draft agenda was approved.

3.    Attendance and Membership

Attendance at working group meetings does not count toward minimum
attendance requirements for X3T10 membership.  Working group meetings are
open to any person or organization directly and materially affected by
X3T10's scope of work.

The following people attended the meeting:

         Name       Organization        Email Address
 ---------------    -------------       -------------
Mr. Bill Dallas     Digital             dallas at zk3.dec.com
Mr. Ken Hallam      Unisys
Mr. David Cressman  Quantum             dcressm at tdh.qntm.com
Mr. Charles Monia   Digital             MONIA at shp.dec.com
Mr. Robert Snively  Sun Micro           bob.snively at sun.com
Mr. Gary R Stephens FSI                 6363897 at mcimail.com
Mr. Rob Sims        HP
Mr. Doug Hagerman   Digital
Mr. Ralph Weber     Symbios Logic       ralph_weber at symbios.com
Mr. George Penokie  IBM                 GOP at RCHUMP3.VNET.COM
Mr. Roger Cummings  DPT                 cummings_roger_dpt.com
Mr. Erich Oetting   Storage Technology  erich_oetting at stortek.com

Total of 12 People Present

4. SMC Topics

4.1 Reserve Element(6) & Release Element(6).

Erich requested the group's concurrence on making changes equivalent to
those made in RESERVE(6) and RELEASE(6) in the RESERVE ELEMENT(6) and
RELEASE ELEMENT(6).  The needed changes were described, essentially
obsoleting the ability to do third-party reservations with the RESERVE
ELEMENT(6) command.  The group discussed Persistent Reservations as related
to medium changer elements.  Bob Snively noted that the persistent
reservations commands define element element reservations, in addition to
logical unit and extent reservations.

4.2 World Wide IDs.

Erich described the current method for defining elements and noted that
READ ELEMENT STATUS does not work in the new larger-configuration world.
The group discussed how the existing world wide unique names can be
incorporated in READ ELEMENT STATUS.  It was noted that the world wide
unique ID returned by READ ELEMENT STATUS must match the one returned by
the vital product data page in the drive logical unit.

The group held a lengthy discussion world wide unique identifiers for media.

5. SSC Topics

5.1 Tape on Serial Interfaces

The group discussed potential changes in fibre channel standards, including
FCP that guarantee ordered delivery.  Several of those present felt that
such changes would not be passed by X3T11.  Other's noted that, in some
cases, we cannot assume what T11's reaction will be until we ask.

Bill Dallas agreed to write descriptions of all three proposed  resolutions
to the problem and distribute it on several email reflectors.

5.2  More than 256 Partitions

Gary Stephens described a concern with volume labeling on partitions.
Adding a volume label to each partition will allow each partition to be
treated as a unique "virtual" volume.  Ken Hallam questioned the proposal
as amounting to defining a file structure on a tape.  This led to a
discussion of permitting larger numbers of partitions.  Gary noted that
more than 256 partitions require an implementation other than the MODE
SENSE/SELECT commands.

5.3 Error Recovery for Tapes on Serial Interfaces.

An extended discussion on detection and recovery of link level errors with
tape drives operating under PLDA was held.  Bob Snivley managed to convince
the group that all link errors can be detected using existing methods
available to PLDA, or an upper level timeout. The PLDA prohibition of data
overlay, and how it affects recovery of write commands when data sequences
are missing was also discussed.

6.   Other Topics

No other topics were discussed.

7.    Meeting Schedule

The next meeting of the SSC/SMC Working Group will be in November in Palm
Springs, CA.  Actual meeting time will be determined by the X3T10 Plenary.

8.    Adjournment

The meeting was adjourned at 11:30 am on Thursday September 12, 1996.

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