Reserve (10); Table 6-95 Reserve (10) Command - Sun Microsystems storagetek sl500 Reference Manual

Reserve (10)

The 10-byte Reserve command (56h) allows the initiator to perform unit
reservations. Unit reservations are reservations of the library as a whole.
Another capability of the Reserve (10) command as opposed to the Reserve (6)
command is the ability to do third party reservations. The third party reservation
allows the reservation of a logical unit within a logical unit on behalf of another
SCSI device.

TABLE 6-95 Reserve (10) Command

Byte 7
0
1 Ignored
2
3
4-6
7 (MSB)
to
8
9
Reserve (10) Command Descriptions:
3rd Pty This field indicates whether the reservation is on behalf of a third party or not:
■
■
The LongID field indicates whether device IDs greater than 255 are required.
LongID
The library only accepts a value of 0. LongIDs are not supported.
Third Party The ID of the third-party device.
Device Id
Parameter List This field indicates the length in bytes of the Parameter List that follows the
command.
Length
96122 • Revision: F
6 5
Operation Code (56h)
3rd Pty
Third Party Device Id
Parameter List Length
Control Byte (00h)
0 = The reservation is on behalf of the calling requester.
1 = The reservation is on behalf of a specified Third party Device Id.
Bit
4 3 2
Reserved
Obsolete
Reserved
Chapter 6 SCSI Commands 225
Reserve (10)
1 0
LongID Obsolete
(0)
(LSB)