| RESERVE UNIT | 16h/56h |
This command enables the host to reserve the drive. Reserving a device is a way of ensuring exclusive access to that device from a single initiator for the period of the reservation.
Once reserved, the drive will execute commands received from the reserving initiator or from the
SENSE, REPORT LUNS, REPORT DENSITY SUPPORT, READ BLOCK LIMITS and RELEASE UNIT.
The INQUIRY, REQUEST SENSE, LOG SENSE, PREVENT/ALLOW MEDIUM REMOVAL (Allow=0), REPORT LUNS, READ BLOCK LIMITS and REPORT DENSITY SUPPORT commands are immune to the effects of a reservation and will continue to execute for all hosts. The RELEASE UNIT command will have GOOD status reported for other hosts, but will have no effect on the reservation.
The reservation will stay in effect until:
•The reserving host sends another RESERVE UNIT command.
•The reserving host sends a RELEASE UNIT command, clearing the reservation.
•A
Illegal Field | Deferred Error | Unit Attention |
If the drive is reserved by some other host then reservation conflict status is reported to the host.
Command descriptor block:
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| 3 | 2 | 1 | 0 |
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164 Commands