HP Surestore 28/48-Slot with DLT7000 Digital Linear Tape SCSI-2 Drive and SCSI - Page 294

NOTE Programmer's Tips TapeAlert Specifications The TapeAlert Log Sense page should be read from a library device at the following times: • At the beginning of a write/read job occurring on a device inside the library, even if a tape is not loaded in that device • Immediately after a fatal error during a write/read job for a device inside the library • At the end of a write/read job on a device inside the library Though not mandatory, the host software may also poll the Log Sense page every 60 seconds while the tape drive/library is idle. However, the host software may use the TapeAlert Mode page to configure other access methods, depending on what options are supported by the tape drive/library. Each time the host software reads the TapeAlert Log page, it should check all 64 flags to discover which are set (there may be more than one). The definitions of the 64 flags are device specific, so one definition is for tape drive/autoloader devices, and one is for stand-alone changer devices (in libraries). For each set flag, the host software should communicate and log the defined error message and severity for that flag to the user. If multiple flags are set simultaneously, they will be displayed together in ascending order of severity. At the beginning of each set of TapeAlert error messages, the tape device/library that initiated them must be identified. For the tape drive media-related flags (flags 4, 7 and 14), the software label of the tape should be included in the TapeAlert error messages so that the user knows which tape has the error. Such information could also be displayed with the messages for other flags if required. The information read in the TapeAlert flags should not in itself cause the software to stop a current backup/restore job. B- 24 Appendix B