Dell PowerVault ML6000 - Manual (Page 61)

PowerVault ML6000 SCSI Reference Guide 51
Persistent Reserve Out – 5Fh
What the Library Does With This Command
The library will perform service actions relative to persistent reservations as requested. This includes
creating and clearing reservations.
Command Usage
This command is used in conjunction with PERSISTENT RESERVE IN to manage persistent reservations.
It can be used to request exclusive access to the device. The PERSISTENT RESERVE IN and
PERSISTENT RESERVE OUT commands should not be used with the RESERVE ELEMENT and
RELEASE ELEMENT commands.
Persistent Reserve Out CDB Format
The PERSISTENT RESERVE OUT CDB format is shown in the following table.
Service Action – This field specifies what reservation action to take as follows:
• 00h Register – Register a reservation key without making a reservation.
• 01h Reserve – Create a persistent reservation of the specified scope and type.
• 02h Release – Releases the selected reservation for the requesting initiator.
• 03h Clear – Clears all reservations keys and all persistent reservations.
• 04h Preempt – Preempt reservations from another initiator.
• 05h Preempt and Abort – Preempt reservations from another initiator and abort all tasks for all
initiators with the specified reservation key.
• 06h Register and Ignore Existing Key – Register a new reservation key and discard existing
reservation key.
Table 48 PERSISTENT RESERVE OUT CDB format
Bit
Byte
7 6 5 4 3 2 1 0
0 Op Code (5Fh)
1 Logical Unit Number Service Action
2 Scope Type
3 Reserved
4 Reserved
5 Reserved
6 Reserved
7
Parameter List Length (18h)
8
9 Control