Virtual TapeServer SCSI-to-FC Adapter User Manual

B-1
Appendix B
Controller LUN Commands
The VT5900-SA supports a set of SCSI-3 commands that can be received as FCP commands over
the Fibre Channel bus. These commands are hereafter referred to as
Controller LUN commands and are executed by the VT5900-SA itself.
When using Controller LUN commands to access general management features, the commands
can be sent to the controller LUN(s) of the VT5900-SA.
It is also possible to initiate Extended Copy operations by sending commands to any tape device
LUN on the VT5900-SA. Thus, there can be numerous concurrent Extended Copy commands
active at one time.
Controller LUNs are addressable in all addressing modes. In SCC mode, there is one controller
LUN. In Auto-Assigned and Indexed modes, there can be up to four configurable controller LUNs.
These four controller LUNs allow the host software to run multiple concurrent Extended Copy
Commands.
Note about the Auto Assigned Maps
Controller LUNs are numbered in sequence following the last device LUN. There is no gap
between device LUNs and controller LUNs.
Note about the Custom Maps
You may place controller LUNs anywhere you like in custom tables.
Additional Notes
Host software must use the Inquiry command in order to determine which VT5900-SA LUNs are
controller LUNs versus which are device LUNs. See the Inquiry and Report LUNs commands in
the General Commands section of this appendix.
The following is a list of the commands that are supported by the controller LUNs. All of these
commands are SCSI-3 commands. Complete definitions of SCSI-3 commands can be found in the
SCSI-3 standard available from the American National Standards Institute (ANSI).
General Commands
• REPORT LUNS
• INQUIRY