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Thu Sep 17 13:27:54 PDT 1998

* From the T10 (formerly SCSI) Reflector (t10 at symbios.com), posted by:
* STEWART_R_WYATT at HP-Boise-om2.om.hp.com
*
     Tape Profile Meeting minutes, 
     St. Petersburg Beach, Florida             T11/98-473v0
     September 15, 1998
     Stewart Wyatt
     
     1. Introductions: Group
     
     Dale LaFollette, StorageTek, called the group to order and began the 
     meeting at 9AM. He had the participants introduce themselves.
     
     2. Approval of this Agenda: T11/98-469v0 Group.
     
     Changed Dave Baldwin to Dave Peterson on item 7. The FC-Tape draft is 
     124vA instead of 124v10. Added a discussion about CRNs. The minutes 
     were approved as modified.
     
     3. Approval of 8/12 Minutes: T11/98-413v0 Stewart Wyatt
     
     Approved
     
     4. Old Action Items: Stewart Wyatt, HP
     
     #1 Dave Baldwin, Emulex, was to revise the ABTS proposal, obtain a 
     document number and post the updated proposal: Dave Baldwin was not 
     able to attend, but Dave Peterson, StorageTek, came prepared with the 
     updated proposal. Agenda item 6. Ongoing.
     #2 Brian Smith, Crossroads, to review Media Changer commands: Brian 
     was not in attendance, but Neal Wanamaker, Crossroads, reported that 
     Brian did not find anything to report.
     #3 Stewart Wyatt to post a copy of the TapeAlert proposal: Completed 
     the document number is T11/98-412v0. 
     #4 Dave Peterson to include TapeAlert in the next version of the SSC: 
     Open.
     #5 Stephen Gold, HP, to post a comment for inclusion of TapeAlert in 
     the SMC: Completed by Stewart Wyatt, HP.
     #6 Participants to review the public/private loop addressing issue. 
     Agenda item 5. Ongoing.
     #7 Rich Taborek/Dal Allan to review what letter ballots are required 
     before going for public review: Dal and Rich were both in attendance. 
     Dal reported that the initial letter ballot would be through T11 
     instead of T11.3 since the T11 ballot is required. Completed.
     
     5. Public/Private Addressing: Jim Coomes, Seagate
     
     Jim Coomes reviewed the issue of having public devices respond to an 
     alias of 00 00 AL_PA as well as their public address of DD AA AL_PA 
     during PLOGI for the benefit of the private devices that are not aware 
     of the public address. Afterwards the private device shall use the DD 
     AA AL_PA to address the public device that is returned in the S_ID of 
     the ACC.
     
     Bob Snively, SUN, questioned this decision. His preference was that 
     the public devices not respond to private devices. But given this 
     situation he preferred to see the public devices continue to respond 
     to the 00 00 AL_PA. Dal Allan, ENDL, and Bob debated the issue in 
     detail. Jim Coomes reported that Bill Martin, Gaddzoox,  had responded 
     to his posting, requesting that devices have only have one address to 
     respond to after login. Dal agreed as did others in the room.
     
     Bob felt like this was requiring a change in private port behavior. 
     Dal and Horst Truestedt, ENDL, argued that the address field was 
     always a 24 bit field. Ed Gardner, Ophidian Designs, argued that this 
     change belongs in the PLDA or the FLA. Jim countered that those 
     documents are closed and done. Jim pointed out that this issue has 
     been publicized on the reflector for months and does not appear to 
     break any existing implementations.
     
     An extension requested by Dave Baldwin was to allow public devices to 
     send PLOGI to all devices on the same loop with a D_ID of 00 00 AL_PA. 
     The public devices will use their DD AA AL_PA address as the S_ID in 
     the ACC. This extension would allow one process for login. Charles 
     Binford, Symbios, pointed out that after accepting the original 
     behavior, it would make the implementation easier to also accept the 
     extension.
     
     Ed Gardiner suggests that this behavior may need to be generalized to 
     ADISC/PDISC. 
     
     Jim agreed to look at the PLDA, FLA and FC-Tape documents to see if 
     other changes are required. He will update his proposal and post it to 
     the reflector.
     
     Bob brought up additional discussion followed about the effect of 
     "Stealth Mode" and the effect of remote initiators logging in with 
     local targets.
     
     Jim Coomes saw the private/public addressing issue as a short term 
     need as he expects all devices to be public soon. Dal Allan assumed 
     that there would be along term need for private loop devices. He 
     suggested that someone needed to define a way (mode page bit) to have 
     the device remain private. Jim thought that was unnecessary. He said 
     that Seagate has had no requests for private only behavior from their 
     customers.
     
     6. ABTS Enhancement Dave Peterson for Dave Baldwin
     
     Ed asked why ABTS came to abort an exchange instead of a sequence. Bob 
     Snively explained that it came out of the FCSI development. 
     
     This proposal allows either the sequence initiator or recipient to 
     issue the ABTS. In class 2 the sequence can be aborted with the ACK. 
     This change was thought necessary for class 3. Some examples were 
     given that suggested that this function may be useful in class 2 such 
     as when an ACK is not returned to the target. 
     
     A discussion followed about the relevance of a sequence recipient 
     sending a ABTS. Since the ABTS doesn't have a payload there was a 
     question about how the sequence to be aborted is specified. Bob 
     suggested eliminating the last paragraph. This would allow setting the 
     bits to select aborting the exchange or sequence and eliminate the 
     proposed change allowing both recipients and initiator to send a ABTS. 
     No need for this functionality was identified. It will be dropped 
     until a need is identified.
     
     Another discussion followed between Bob and Dal about how an initiator 
     can signal to a target an error in a long read and whether that need 
     is legitimate.
     
     7. FCP Model Enhancement: Dave Peterson
     
     The enhancement is Annex C in Rev 1.09 of the profile. Dave had posted 
     the annex to the reflector independently. 
     
     Ed would like to request the FCP_CONF by NOT making the FCP_RSP not 
     the last frame of the sequence. After some discussion, he decided that 
     this would preclude linked commands.
     
     Dave was reminded that this text must be normative and was suggested 
     to add a note that it will be replaced by FCP2.
     
     Dal Allan was concerned about the text that allowed the target to 
     assume that the FCP_CONF for a given exchange was lost and proceed 
     without error recovery if it receives a command with the same OX_ID. 
     After some discussion, Dal Allan and Matthew Wakeley, HP, felt that 
     the target should not accept the new exchange. (Reject in class 2 or 
     drop the frame in class 3.) The last sentence of the proposal was 
     changed to read that..."the target shall follow the rules as defined 
     in the FC-PH in regards to duplicate exchange management".
     
     Dave presented an overhead with the FCP_CONF model included in the 
     posting and the last draft which he had already started marking up. 
     The group proposed a number of other changes. Bob Snively wanted to 
     remove the reference to dual porting which Rob Basham, IBM, had 
     requested. He also questioned the value of item b and its paragraph 
     which suggested that FCP_CONF is needed for initialization. No one 
     present could see why this was an exceptional requirement. Rob was not 
     present to defend his position.
     
     8. Required SCSI Commands Cont. T11/98-375v1 Dale Lafollette
     
     Doug Hagerman, Digital now Compaq, sent a memo to Dave LaFollette 
     requesting that the SCSI Tape Device Commands follow the PLDA pattern 
     which includes an "allowable" category. Bob Snively has argued against 
     using allowable as he believes it defeats interoperability. A long 
     discussion followed about the meanings of the various words and the 
     effect of implementing a "prohibited" feature. The decision was to use 
     a single column for the SCSI Tape Commands table for both hosts and 
     tapes.
     
     Only two words will be used to describe a commands support in the 
     profile. The first is Invokable which is defined to mean that the 
     Initiator is permitted to execute and target is required to support 
     the command. The second is Prohibited using the FLA definition which 
     is currently in the profile.
     
     The group reviewed the commands looking at which fields should be 
     supported. The results will be included in the next revision of the 
     profile.
     
     8a CRN Review
     
     Charles Binford noted that Annex D states that a LUN Reset Task 
     Management function will reset the CRN to 1. He asked how the LUN 
     reset is performed and did not get an answer as no one seemed to know. 
     He also thought this should be included in the clearing effects table.
     
     9. FC-Tape Draft Review: T11/98-124vA
     
     Charles Binford asked about the FCP_DL and residuals. After some 
     discussion it was decided that when executing a write command to 
     calculate the transfer length first and if it doesn't match the FCP_DL 
     length to reject the command. Eric Oetting noted that the behavior 
     required for residuals is described in the SSC read and write command 
     descriptions. Dave Peterson suggested requiring that the FCP_DL equal 
     the transfer length.
     
     10. T10 New Business: Group
     
     None.
     
     11. T11 New Business: Group
     
     New schedule for FC-Tape: 
     Sept. 24: FC-Tape draft completed. Reflector posting stating our 
     intention to request a letter ballot through T11.
     Oct 7: FC-Tape working group resolves any new issues with Sept. 24th 
     FC-Tape draft.
     Oct 8: Request a letter ballot for the Oct 7th version of the draft 
     unless the 2 week rule is called. If it is, then request a letter 
     ballot on the Sept. 24th version.
     Letter ballot starts some days latter.
     30 days after the letter ballot closes, assumed to be after November 
     T10 meetings, the editor starts reviewing letter ballot comments.
     Dec 16 T11 working group meeting reviews our editors comments on the 
     letter ballot comments
     
     12. Review New Action Items: Stewart Wyatt
     
     #1 Jim Coomes agreed to look at the PLDA, FLA and FC-Tape documents to 
     see if other changes are required to support the proposed changes in 
     public/private addressing. Jim will update proposal and post it to the 
     reflector.
     
     #2 Dave Peterson to get a document number for the ABTS proposal, 
     update it and upload it to the web site
     
     #3 Dale LaFollette will complete the SMC command and parameter review 
     for input to the document.
     
     #3 Dave Peterson will update FC-Tape with this meetings comments by 
     September 24th.
     
     #4 Dale LaFollette will post the FC_Tape schedule and a request for 
     review in preparation for the letter ballot when Dave completes the 
     profile.
     
     13. Adjournment: Group 5 PM

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