To: "t10@t10.org" <t10@t10.org> Subject: ADT-2: SCSI Command IU to Initiator Only port From: Kevin D Butt <kdbutt@us.ibm.com> Date: Mon, 26 Nov 2007 13:19:45 -0700 X-Message-Number: 8266 Formatted message: HTML-formatted message Attachment #1: banther_michael-3.vcf 07-438r0 suggests that we change "acts as" a SCSI target/initiator port to "is" a SCSI target/initiator port. and that we add the following to ADT-2: If a port that does not support SCSI target functions receives a SCSI Command IU or a SCSI Task Management IU, then it shall transmit a NAK IU with a status code of UNSUPPORTED FRAME TYPE FOR SELECTED PROTOCOL (see table 14) and discard the IU. Note x: The exchange originator should not interpret this response as an indication that the port does not have SCSI target port capabilities, only that it does not have SCSI target port capabilities enabled at this time (see 4.1). Discussion about "acts as" vs "is" First, I think "acts as" is more correct than "is". A port that is a SCSI target/initiator port (this term does not exist in SAM-4) acts as a SCSI initiator port and a SCSI target port. SAM-4 states: << Each instance of a SCSI Port class shall contain: a) one SCSI target port that shall contain: A) one task router; b) one SCSI initiator port; or c) both. >> SAM-3 states: << 3.1.94 SCSI initiator port: A SCSI initiator device object that acts as the connection between application clients and the service delivery subsystem through which requests, indications, responses, and confirmations are routed. In all cases when this term is used it refers to an initiator port or a SCSI target/initiator port <<operating as>> a SCSI initiator port. and 3.1.99 SCSI target port: A SCSI target device object that contains a task router and acts as the connection between device servers and task managers and the service delivery subsystem through which indications and responses are routed. When this term is used it refers to a SCSI target port or a SCSI target/initiator port <<operating as>> a SCSI target port. and 3.1.101 SCSI target/initiator port: A SCSI device resident object that has all the characteristics of a SCSI target port and a SCSI initiator port. >> Discussion about adding the suggested text: The issue that this proposal intends to solve is that of a port receiving a command IU when that port is an initiator port only or that is an initiator/target port that has not yet been configured to act as a target port. One of the concerns about what is returned is that the port initiating this command IU not take the rejection to mean that this port will never accept a command IU. There are really two behaviors that a plausible. One behavior is that mentioned in the proposal of the transport layer returning a NAK IU with a status code of UNSUPPORTED FRAME TYPE FOR SELECTED PROTOCOL. The other is to treat the port as being a target port but not having a valid logical unit so the response would be at a higher layer. It seems to me that returning a LOGICAL UNIT NOT CONFIGURED would be more accurate. Further it does not imply that the logical unit does not exist or is not supported. It just implies that it needs configured before it can be communicated with. This is exactly the scenario we are in. The one concern I have with this approach is that no LU exists and no well-known LU either. Thanks, Kevin D. Butt SCSI & Fibre Channel Architect, Tape Firmware MS 6TYA, 9000 S. Rita Rd., Tucson, AZ 85744 Tel: 520-799-2869 / 520-799-5280 Fax: 520-799-2723 (T/L:321) Email address: kdbutt@us.ibm.com http://www-03.ibm.com/servers/storage/ "Banther, Michael" <michael.banther@hp.com> Sent by: owner-t10@t10.org 11/26/2007 10:39 AM To "t10@t10.org" <t10@t10.org> cc Subject ADI-2 teleconference The ADI-2 working group will hold an ad-hoc teleconference on 28 November 2007 starting at 8:00 AM PST and concluding at 10:00 AM PST. You can find the agenda, including contact details, at http://www.t10.org/ftp/t10/document.08/08-004r0.pdf. Regards, Michael Banther Tel. +44 117 312 9503 Hewlett-Packard Limited registered Office: Cain Road, Bracknell, Berks RG12 1HN Registered No: 690597 England The contents of this message and any attachments to it are confidential and may be legally privileged. If you have received this message in error, you should delete it from your system immediately and advise the sender. To any recipient of this message within HP, unless otherwise stated you should consider this message and attachments as "HP CONFIDENTIAL".