User Manual

SCSI Commands Reference Manual, Rev. J 98
www.seagate.com Direct Access Block commands (SPC-5 and SBC-4)
ACC (Access Controls Coordinator) bit
1 An Access Controls Coordinator (ACC) bit set to one indicates that the SCSI target device contains an access controls coordinator that
may be addressed through this logical unit.
0 An ACC bit set to zero indicates that no access controls coordinator may be addressed through this logical unit. If the SCSI target device
contains an access controls coordinator that may be addressed through any logical unit other than the ACCESS CONTROLS well known
logical unit, then the ACC bit shall be set to one for LUN 0.
TPGS (Target Port Group Support) field
The contents of the target port group support (TPGS) field (see table 63) indicate the support for asymmetric logical unit access.
3PC (Third-Party Copy) bit
1 A Third-Party Copy (3PC) bit set to one indicates that the SCSI target device supports third-party copy commands such as the EXTENDED
COPY command.
0 A 3PC bit set to zero indicates that the SCSI target device does not support such commands.
PROTECT bit
0 A PROTECT bit set to zero indicates that the logical unit does not support protection information (i.e. type 0) (see SPC-5 and SBC-4).
1 A PROTECT bit set to one indicates that the logical unit supports type 1 protection, type 2 protection, or type 3 protection (see SBC-4).
The SPT field in the Extended INQUIRY Data VPD page (see 5.4.9) indicates which type of protection the logical unit supports.
ENCSERV (Enclosure Services) bit
1 An Enclosure Services (ENCSERV) bit set to one indicates that the SCSI target device contains an embedded enclosure services compo-
nent. See SES for details about enclosure services, including a device model for an embedded enclosure services device.
0 An ENCSERV bit set to zero indicates that the SCSI target device does not contain an embedded enclosure services component.
MULTIP (Multi Port) bit
1 A Multi Port (MULTIP) bit set to one indicates that this is a multi-port (two or more ports) SCSI target device and conforms to the SCSI
multi-port device requirements found in the applicable standards (e.g., SAM-5, a SCSI transport protocol standard and possibly provi-
sions of a command standard).
0 A MULTIP bit set to zero indicates that this SCSI target device has a single port and does not implement the multi-port requirements.
CMDQUE (Command Queuing) bit
If the logical unit does not support the BQUE bit, CMDQUE bit shall be set to one indicating that the logical unit supports the task management
model (see SAM-5).
Table 63 Target Port Group Support codes
Code Description
00b
The SCSI target device does not support asymmetric logical unit access or supports a form of asymmetric access that
is vendor specific. Neither the REPORT TARGET GROUPS nor the SET TARGET GROUPS commands is supported.
01b
Only implicit asymmetric logical unit access (see SPC-5) is supported. The SCSI target device is capable of changing
target port asymmetric access states without a SET TARGET PORT GROUPS command. The REPORT TARGET PORT
GROUPS command is supported and the SET TARGET PORT GROUPS command is not supported.
10b
Only explicit asymmetric logical unit access (i.e., the TPGS field contains 10b or 11b) is supported. The SCSI target
device only changes target port asymmetric access states as requested with the SET TARGET PORT GROUPS com
-
mand. Both the REPORT TARGET PORT GROUPS command and the SET TARGET PORT GROUPS command are sup-
ported.
11b
Both explicit and implicit asymmetric logical unit access are supported. Both the REPORT TARGET PORT GROUPS com-
mand and the SET TARGET PORT GROUPS commands are supported.