Date: April 05, 1990 X3T9.2/90-059R0 To: X3T9.2 Committee (SCSI) From: George Penokie (IBM) Subject: Reserve Command conflicts with Direct-Access Model Problem: In section 8.1.7. Reservation, page 8-6, first paragraph, the sentence 'The FORMAT UNIT, PREVENT ALLOW MEDIUM REMOVAL, REZERO UNIT, and START STOP UNIT commands will generate a reservation conflict...' is in conflict with section 8.2.12.1. Logical Unit Reservation, page 8-38, last paragraph. That paragraph states '... any command on the reserved logical unit other than an INQUIRY, REQUEST SENSE, ALLOW MEDIUM REMOVAL, RESERVE, or a RELEASE command then the command shall be rejected with RESERVATION CONFLICT status.' It looks like the allow option of the PREVENT ALLOW MEDIUM REMOVAL command should not be in the list of commands in the model. It, also, appears that the RESERVE command should not be in the list in section 8.2.12.1. If anyone can think of a reason for putting the RESERVE command in the list of commands which are not rejected with RESERVATION CONFLICT lets talk about it. Purposed Solution: In section 8.1.7. Reservation, page 8-6, change the first paragraph and the second paragraph to read as follows: 'The FORMAT UNIT, REZERO UNIT, START STOP UNIT, and PREVENT ALLOW MEDIUM REMOVAL (with the prevent option selected) commands will generate a reservation conflict if any other initiator has an extent reservation on a direct-access device. The INQUIRY, REQUEST SENSE, and PREVENT ALLOW MEDIUM REMOVAL (with the allow option selected) commands are not affected by any kind of reservation.' In section 8.2.12.1. Logical Unit Reservation, page 8.38, change the last paragraph to read as follows: 'If, after honoring the reservation, any other initiator attempts to perform any command on the reserved logical unit other than an INQUIRY, REQUEST SENSE, PREVENT ALLOW MEDIUM REMOVAL (with the allow option selected), and RELEASE command then the command shall be rejected with RESERVATION CONFLICT status.'