HP Surestore 28/48-Slot with DLT7000 Digital Linear Tape SCSI-2 Drive and SCSI - Page 284

Disconnect Timeouts

Page 284 highlights

Table B-3 CAUTION Programmer's Tips Modifying the SCSI Driver Necessary Autochanger SCSI Commands Command Optional Exchange Medium Mode Sense / Select Position To Element Prevent/Allow Medium Removal Receive Diagnostic Result Log Sense / Select Report Luns Release Reserve Rezero Unit Rotate Mailslot Persistent Reserve OP Code A6H 1AH 2BH 1EH 1CH 4CH, 4DH A0H 17H 16H 01H 0CH 5EH, 5FH For more information on the I/O subsystem, refer to Chapters 2 and 3 in the HP-UX Driver Development Guide for the Hewlett-Packard version (HP Part No. 98577-90001). Disconnect Timeouts The following commands will cause a SCSI disconnect. It is useful to know what the maximum times for disconnect are so driver timeouts can be set appropriately: In Table B-4, the maximum disconnect time is represented by the nominal number of seconds plus the number of levels of error recovery times 60. Though the maximum disconnect time can be rather long, we strongly recommend using this time over the nominal timeout. If the timeout is too short, the command will be aborted and a I/O request B- 14 Appendix B

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B-14
Appendix B
Programmer’s Tips
Modifying the SCSI Driver
For more information on the I/O subsystem, refer to Chapters 2 and 3 in
the HP-UX Driver Development Guide for the Hewlett-Packard version
(HP Part No. 98577-90001).
Disconnect Timeouts
The following commands will cause a SCSI disconnect. It is useful to
know what the maximum times for disconnect are so driver timeouts can
be set appropriately:
CAUTION
In Table B-4, the maximum disconnect time is represented by the
nominal number of seconds plus the number of levels of error recovery
times 60. Though the maximum disconnect time can be rather long, we
strongly recommend using this time over the nominal timeout. If the
timeout is too short, the command will be aborted and a I/O request
Optional
Exchange Medium
A6H
Mode Sense / Select
1AH
Position To Element
2BH
Prevent/Allow Medium
Removal
1EH
Receive Diagnostic Result
1CH
Log Sense / Select
4CH, 4DH
Report Luns
A0H
Release
17H
Reserve
16H
Rezero Unit
01H
Rotate Mailslot
0CH
Persistent Reserve
5EH, 5FH
Table B-3
Necessary Autochanger SCSI Commands
Command
OP Code