See ”read-while-write” | HP LTO 4 SAS, LTO 4 FC, LTO 4 SCSI specification

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HP LTO 4 SAS, LTO 4 FC, LTO 4 SCSI manual see ”read-while-write”

Contents

volume 2 software integration LTO 4 FC, SCSI and SAS drivesHP LTO Ultrium tape drives technical reference manual HP restricted Legal and notice information Contents 1 Designing backup applications2 Configuration and initialization 3 Use of tapes 5 Supporting Ultrium features 4 Factors affecting performance 6 Sense keys and codes 7 Exception handling HP restricted Related documents Documentation mapDocuments specific to HP Ultrium drives Drives-general Installation and configuration OperationCartridges Interface Maintenance and troubleshooting Dealing with errors LTO Ultrium features General documents and standardization 1 Designing backup applications Non-immediate commandsOptimizing performance Large data transfer size Cleaning tape heads Managing the use of tapesInformation in Cartridge Memory Monitoring tape use Design goals for LTO backup applications Diagnostic logsTapeAlert Displaying drive information Include the capability to download firmware Operating system drivers 2 Configuration and initializationInquiry string recovery SCSI protocol, regardless of transport or interface type Example16 Configuration and initialization Supporting additional LUNs Support for additional LUNEnabling additional LUN support 18 Configuration and initialization Using Cartridge Memory attributes Using MODE SENSE3 Use of tapes LTO cartridge memory Interpreting Log Sense data Tape status and capacityFinding the remaining capacity CDB fields Using the SET CAPACITY commandCommand descriptor block Changes to SCSI commands WORM mediaHow WORM media works New additional sense codes and TapeAlert flags Error Usage page ERASE commands rejectedSET CAPACITY command Re-writing media labels Unique media identifier Using CM to check tape integrityBehavior with a missing or inconsistent EOD value Barcode support Responding to Cartridge Memory dataLoad count RWW retry counts Corrective action 4 Factors affecting performance Ways of optimizing performanceDetecting the drive’s speed Ensuring the recommended minimum transfer sizes Using Cartridge Memory instead of tape headers Using the Performance Log page for diagnosing problemsTime-out values Media type identification Host-related factors Recommended support of log pagesFactors affecting performance Example Recommendationwhere possible or a reasonably sized RAID system. More disks means makes sense to split heavily used FC cards across separate PCI busses Drive-related factors Do not interleave write commands with other commands, such as READ Format-related factors Page 34 Factors affecting performance 5 Supporting Ultrium features Cartridge Memory LTO-CMAutomation interface Further information Automation/Device Interface ADI Slave to a library controller Automation Control Interface ACIModes of usage through ACI SCSI pass-through mode ACI command setACI commands that affect drive streaming performance New features in ACI Backward compatibility SCSI command Encryption support Further details Supporting the ACI protocolRecommended ACI time-out values 42 Supporting Ultrium features Recommended power-up sequence Treatment of reserved fields Recommended load-unload configuration Firmware upgrade via tape Recommended Get Drive Status polling frequencyACI protocol communications retry Upgrading the drive firmware Firmware upgrade via the primary host interface Firmware upgrade via ACILibrary firmware upgrade via tape Handling irregular cartridges Cleaning cartridge HP-configured or Universal Expired cleaning cartridge HP-configured or UniversalNon-HP Ultrium 1 cleaning cartridge Unreadable data cartridge Valid firmware upgrade cartridge Data cartridge with unreadable CMCartridge fails to seat or load Cartridge cannot be loaded Frequently asked questions CleaningInvalid firmware upgrade cartridge Is there separate firmware for drives intended to go into libraries? Backup software Resetting drivesResetting via the ACI Reset command Resetting using the ACIRSTL line Accessing Cartridge Memory without threading the tape Controlling data compressionOther mode page information Buffer size at EW-EOM Rewind on reset Write delay timePartition size 52 Supporting Ultrium features 6 Sense keys and codes Sense keys-actions to takeAction Console Message “3h-MEDIUM ERROR” on page 62 . Also see the Media Access For additional sense codes, see “3h-MEDIUM ERROR” onlog the error, terminate I/O to the drive, and pass the appropriate error to the calling application Action Console MessageAction Console Message page Additional sense codes-actions to take PhysicalEnd-of-Tape reached, unable to fit 0h-NO SENSE 1h-RECOVERED ERROR 2h-NOT READY The software must issue a LOAD before media access LUN not accessible, port inThe command cannot be executed because the specified 60 Sense keys and codes mechanism tests are being executed. When the tests are 62 Sense keys and codes 3h-MEDIUM ERRORA READ , SPACE , WRITE or WRITE FILEMARKS command Send a console message that an unrecovered error on and the drive. Based on this, ask the user to clean the 64 Sense keys and codes Send a message to the console indicating that there is The current command such as READ, SPACE, REWIND 66 Sense keys and codes 4h-HW ERROR 68 Sense keys and codes 5h-ILLEGAL REQUESTA MODE SELECT parameter list sent to the drive contains 6h-UNIT ATTENTION persistent reservation using the PERSISTENT RESERVE OUTallowed to execute. In other words, some commands can 32 initiators to register, using PERSISTENT RESERVE OUT Action service action removed all reservations and the persistent A PERSISTENT RESERVE OUT command was executedWRITE BUFFER or MAINTENANCE OUT command A SET DEVICE IDENTIFIER command has been successful 7h-DATA PROTECTION Code 8h-BLANK CHECK related to a missing EOD data set. The most likely cause Bh-ABORTED COMMANDREAD BUFFER command 76 Sense keys and codes Dh-VOLUME OVERFLOWA WRITE or WRITE FILEMARKS command has encountered Typical escalation procedure 1. Retrieve fault information3. Allow the user to try recovery 4. Allow the user to reset devices Monitoring the condition of the drive and media Supporting TapeAlert Flags TypePage Page Page Page Page Page Page Designing software to use the TapeAlert log TapeAlert models TapeAlert informational exception usage model Reading the TapeAlert logTapeAlert polling usage model Supporting OBDR One-Button Disaster Recovery OBDRResponding to the ‘Clean’ LED Providing pass-through mode Requirements for drivers and logical device managers Glossary see ”read-while-write” Index Page Page HP restricted