To: Gary.Franco@Emulex.Com Cc: owner-t10@t10.org, t10@t10.org Subject: Re: Type 3 protection From: George Penokie <gop@us.ibm.com> Date: Mon, 27 Nov 2006 08:49:06 -0600 X-Message-Number: 7402 Formatted message: HTML-formatted message Gary, The rules for checking are in the footnotes. For example in table 71 footnote j describes the rules for checking the Reference Tag: If type 1 protection is enabled, the device server checks the logical block reference tag by comparing it to the lower 4 bytes of the LBA associated with the logical block. If type 2 protection or type 3 protection is enabled, the device server checks the logical block reference tag if it has knowledge of the contents of the LOGICAL BLOCK REFERENCE TAG field. If type 2 protection is enabled, then this knowledge may be acquired through the EXPECTED INITIAL LOGICAL BLOCK REFERENCE TAG field in a WRITE (32) command (see 5.29). If type 3 protection is enabled, then the method for acquiring this knowledge is not defined by this standard. That footnote is telling you that for type 3 protection the target only check the reference tag if the target knows what the content is be some means not defined by the standard. Also, sending out a message on this reflector that states the information is "confidential information of Emulex Corporation" is a not a good way to get responses. In the future any such messages received on my machine will automatically be deleted. Bye for now, George Penokie Dept 9A8 030-3 A410 E-Mail: gop@us.ibm.com Internal: 553-5208 External: 507-253-5208 Gary.Franco@Emulex.Com Sent by: owner-t10@t10.org 11/25/2006 07:17 AM To <t10@t10.org> cc Subject Type 3 protection I would like a clarification on the correct implementation for Type 3 checking when dealing with WRPROTECT/RDPROTECT/VRPROTECT . In SBC-3r07 clause 4.17.2.5 Type 3 protection states: Type 3 protection: a) defines the content of the LOGICAL BLOCK GUARD field within the logical blocks of the data-in buffer and/or data-out buffer; b) does not define the content of the LOGICAL BLOCK APPLICATION TAG field; and c) does not define the content of the LOGICAL BLOCK REFERENCE TAG field. However in the individual command descriptors, WRITE(10) for example, Table 71 ? WRPROTECT field indicates that both the Application Tag and Reference Tag should be checked. Since both of these DIF items are not defined for Type 3 protection, I assume that for Type 3 protected devices these fields should not be checked at all. Can someone clarify? Thanks in advance __________________________________ Gary Franco Consultant Engineer Emulex Network Systems 972-671-7433 Dallas Office 972-671-7435 Dallas Office Fax 720-652-6387 Longmont Colorado Office 720-494-1817 Longmont Colorado Office Fax 972-839-5694 Cell Phone Today's Quote Be who you are and say what you feel because those who mind don't matter and those who matter don't mind. -Dr. Seuss Thank you.