Sony SDX-800V/R User Manual

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RESERVE UNIT 
6.Command Specification
 
SONY AIT-3Ex drive SDX-800V series Ver.1.1 
 
6-95 
 
6.23. RESERVE UNIT (6/10) 16h and 56h 
Table 6-91: RESERVE UNIT (6) CDB format 
Bit 
Byte 
7 6 5 4 3 2 1 0 
Operation Code (16h) 
Reserved Obsolete 
Obsolete 
Reserved 
Reserved 
Control 
Table 6-92: RESERVE UNIT (10) CDB format 
Bit 
Byte 
7 6 5 4 3 2 1 0 
Operation Code (56h) 
Reserved 3rdPty 
Reserved 
Long 
ID 
Reserved
Obsolete 
Third Party Device ID 
Reserved 
Reserved 
Reserved 
7-8 
Parameter List Length 
Control 
The RESERVE (6/10) command reserves the Logical Unit for exclusive use by the requesting initiator or one other 
specified SCSI device (3
rd
 party). The RELEASE (6/10) command is used to release the Logical Unit if it was 
reserved by the requesting initiator using a RESERVE (6/10) command and is still in the reserved state.  
See PERSISTENT RESERVE OUT/IN for an alternate reservation system. The PERSISTENT RESERVE OUT 
command cannot be used to release a reservation generated by the RESERVE (6/10) commands. 
Third party reservation management operations are only allowed using RESERVE (10) and RELEASE (10). 
Logical Unit reservation management operations are allowed using RESERVE (6/10) and RELEASE (6/10). 
The reservation remains in effect until one of the following conditions is met: 
- The initiator that made the reservation sends another RESERVE UNIT command. 
- The Logical Unit is released by a RELEASE (6/10) command from the same initiator. 
- The Logical Unit in a 3
rd
 Party reservation is released by a RELEASE (10) command from the same initiator. 
- A TARGET RESET or LOGICAL UNIT RESET Task Management function is received from any initiator. 
The occurrence of the last two conditions is indicated by the Logical Unit returning a CHECK CONDITION status with 
a sense key of UNIT ATTENTION on the next command following the condition.  
It is not an error for an initiator to issue a new RESERVE (6/10) command to the Logical Unit when the Logical Unit 
is currently reserved by that same initiator. If the Logical Unit has previously been reserved by another initiator, then 
the Logical Unit terminates the command with RESERVATION CONFLICT status. 
If, after honoring the reservation, any other initiator then attempts to perform any command except INQUIRY, 
REQUEST SENSE, REPORT LUNS or RELEASE UNIT, then the command is rejected with a RESERVATION 
CONFLICT status. A RELEASE UNIT command issued by another initiator will be ignored by that reserved logical 
unit. 
Obsolete: These fields are not supported and must be set to ZERO. 
If this field is not ZERO, the command is terminated with CHECK CONDITION status and the Sense Key is set to ILLEGAL REQUEST. The 
Additional Sense Code is set to INVALID FIELD IN CDB.