HP LTO 4 FC, LTO 4 SCSI Monitoring the condition of the drive and media, Supporting TapeAlert

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Monitoring the condition of the drive and media

5.Parallel SCSI only: Allow the System Supervisor or support person to perform a controlled hard SCSI Bus Reset.

If the LOGICAL UNIT RESET Task Management function fails to clear the problem, the System Supervisor or technical support person should be able to perform a controlled hard SCSI Bus Reset as follows:

•Lock other users out cleanly.

•Go to a minimal-system single-user mode.

•Close all applications.

•Execute a hard SCSI Bus Reset.

The process should not require a complete shutdown and reboot of the system.

Monitoring the condition of the drive and media

Through TapeAlert, an HP LTO Ultrium tape drive constantly monitors the condition of the mechanism and media, and presents the results in a form that host software can readily use and users can easily understand.

You can find a general description of TapeAlert in the diagnostics section of the User Guide.

Supporting TapeAlert

HP has refined the TapeAlert standard to include the Predictive Failure flag. If the drive sets this flag, the host should display a message that the drive is “about to fail and should be replaced”. There should be no impact on ISV software if the TapeAlert standard is already fully supported.

NOTE: Reading the TapeAlert log clears all the flags, as defined in the TapeAlert specification.

The TapeAlert Log page consists of 64 flags that indicate potential problems with the drive, and that allow host software to suggest appropriate corrective action to the user. For example, if Flag 20 (“Clean Now”) is set, the software should advise the user to clean the tape heads.

The drive maintains both SSC and ADC TapeAlert flags because the two standards state different clearing conditions.

•The drive maintains separate copies of the SSC TapeAlert flags for each port. These are only cleared when a port retrieves its TapeAlert flags with a LOG SENSE command with page code 2Eh, provided the TAPLSD (TapeAlert Prevent LOG SENSE Deactivation) mode parameter is zero in the Device Configuration Extension mode page.

•The drive also maintains a set of ADC TapeAlert flags, which are shared by each port. The ADC TapeAlert flags are not cleared when a port retrieves them with a LOG SENSE command with page code 12h.

See Chapter 4 of Volume 3, SCSI Interface, of the HP Ultrium Technical Reference Guide for details of the TapeAlert log page.

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Contents HP LTO Ultrium tape drives technical reference manual volume 2 software integrationLTO 4 FC, SCSI and SAS drives HP restrictedLegal and notice information 2 Configuration and initialization Contents1 Designing backup applications 3 Use of tapes5 Supporting Ultrium features 4 Factors affecting performance6 Sense keys and codes 7 Exception handlingHP restricted Documents specific to HP Ultrium drives Related documentsDocumentation map Drives-generalCartridges Installation and configurationOperation InterfaceMaintenance and troubleshooting Dealing with errorsLTO Ultrium features General documents and standardizationOptimizing performance 1 Designing backup applicationsNon-immediate commands Large data transfer sizeInformation in Cartridge Memory Cleaning tape headsManaging the use of tapes Monitoring tape useTapeAlert Design goals for LTO backup applicationsDiagnostic logs Displaying drive informationInclude the capability to download firmware 2 Configuration and initialization Inquiry string recoveryOperating system drivers Example 16 Configuration and initializationSCSI protocol, regardless of transport or interface type Support for additional LUN Enabling additional LUN supportSupporting additional LUNs 18 Configuration and initialization 3 Use of tapes Using Cartridge Memory attributesUsing MODE SENSE LTO cartridge memoryTape status and capacity Finding the remaining capacityInterpreting Log Sense data Using the SET CAPACITY command Command descriptor blockCDB fields How WORM media works Changes to SCSI commandsWORM media New additional sense codes and TapeAlert flagsSET CAPACITY command Error Usage pageERASE commands rejected Re-writing media labelsUsing CM to check tape integrity Behavior with a missing or inconsistent EOD valueUnique media identifier Responding to Cartridge Memory data Load countBarcode support RWW retry counts Corrective actionDetecting the drive’s speed 4 Factors affecting performanceWays of optimizing performance Ensuring the recommended minimum transfer sizesTime-out values Using Cartridge Memory instead of tape headersUsing the Performance Log page for diagnosing problems Media type identificationRecommended support of log pages Factors affecting performanceHost-related factors where possible or a reasonably sized RAID system. More disks means ExampleRecommendation makes sense to split heavily used FC cards across separate PCI bussesDrive-related factors Do not interleave write commands with other commands, such as READFormat-related factors Page 34 Factors affecting performance Automation interface 5 Supporting Ultrium featuresCartridge Memory LTO-CM Further informationAutomation/Device Interface ADI Automation Control Interface ACI Modes of usage through ACISlave to a library controller ACI command set ACI commands that affect drive streaming performanceSCSI pass-through mode New features in ACI Backward compatibilitySCSI command Encryption support Recommended ACI time-out values Further detailsSupporting the ACI protocol 42 Supporting Ultrium featuresRecommended power-up sequence Treatment of reserved fieldsRecommended load-unload configuration ACI protocol communications retry Firmware upgrade via tapeRecommended Get Drive Status polling frequency Upgrading the drive firmwareLibrary firmware upgrade via tape Firmware upgrade via the primary host interfaceFirmware upgrade via ACI Handling irregular cartridgesNon-HP Ultrium 1 cleaning cartridge Cleaning cartridge HP-configured or UniversalExpired cleaning cartridge HP-configured or Universal Unreadable data cartridgeCartridge fails to seat or load Valid firmware upgrade cartridgeData cartridge with unreadable CM Cartridge cannot be loadedInvalid firmware upgrade cartridge Frequently asked questionsCleaning Is there separate firmware for drives intended to go into libraries?Resetting via the ACI Reset command Backup softwareResetting drives Resetting using the ACIRSTL lineOther mode page information Accessing Cartridge Memory without threading the tapeControlling data compression Buffer size at EW-EOMPartition size Rewind on resetWrite delay time 52 Supporting Ultrium featuresAction 6 Sense keys and codesSense keys-actions to take Console Messagelog the error, terminate I/O to the drive, and pass the appropriate “3h-MEDIUM ERROR” on page 62 . Also see the Media AccessFor additional sense codes, see “3h-MEDIUM ERROR” on error to the calling applicationAction ActionConsole Message Console MessageConsole Message End-of-Tape Additional sense codes-actions to takePhysical reached, unable to fit0h-NO SENSE 1h-RECOVERED ERROR 2h-NOT READYThe command cannot be executed because the specified The software must issue a LOAD before media accessLUN not accessible, port in 60 Sense keys and codesmechanism tests are being executed. When the tests are 3h-MEDIUM ERROR A READ , SPACE , WRITE or WRITE FILEMARKS command62 Sense keys and codes Send a console message that an unrecovered error on and the drive. Based on this, ask the user to clean the64 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 codes4h-HW ERROR 5h-ILLEGAL REQUEST A MODE SELECT parameter list sent to the drive contains68 Sense keys and codes allowed to execute. In other words, some commands can 6h-UNIT ATTENTIONpersistent reservation using the PERSISTENT RESERVE OUT 32 initiators to register, using PERSISTENT RESERVE OUTAction WRITE BUFFER or MAINTENANCE OUT command service action removed all reservations and the persistentA PERSISTENT RESERVE OUT command was executed A SET DEVICE IDENTIFIER command has been successful7h-DATA PROTECTION Action 8h-BLANK CHECK Bh-ABORTED COMMAND READ BUFFER commandrelated to a missing EOD data set. The most likely cause Dh-VOLUME OVERFLOW A WRITE or WRITE FILEMARKS command has encountered76 Sense keys and codes 3. Allow the user to try recovery Typical escalation procedure1. Retrieve fault information 4. Allow the user to reset devicesMonitoring the condition of the drive and media Supporting TapeAlertFlags TypePage Page Page Page Page Page Page Designing software to use the TapeAlert log TapeAlert modelsReading the TapeAlert log TapeAlert polling usage modelTapeAlert informational exception usage model One-Button Disaster Recovery OBDR Responding to the ‘Clean’ LEDSupporting OBDR Providing pass-through mode Requirements for drivers and logical device managersGlossary see ”read-while-write” Index Page Page HP restricted
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