HP LTO 4 SCSI, LTO 4 FC, LTO 4 SAS manual Reading the TapeAlert log, TapeAlert polling usage model

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In addition, the application can determine which TapeAlert flags are supported by the device server through the TapeAlert supported flags VPD page (B2h).

TapeAlert polling usage model

In this model, the application configures the device server by setting the TASER bit in the Device Configuration Extension mode page (10h) to one.

The device server does not notify the application that a TapeAlert flag has changed. The application can read the TapeAlert log page or the TapeAlert Response log page at any time (for example, polling every x seconds) or upon certain relevant operations:

•Before loading a tape

•Immediately after detecting an unrecoverable error

•Before unloading a tape

•At the end of a data transfer

TapeAlert informational exception usage model

In this model, the application configures the device server by setting the TASER bit in the Device Configuration Extension mode page (10h) to zero, and in the Informational Exceptions mode page, by setting the DExcpt bit to zero and the TEST bit to zero.

The device server notifies the application that a TapeAlert flag has been activated by reporting and informational exception condition on the next SCSI command, with additional sense of 5D00h (failure prediction threshold exceeded). If the device server has been configured to return descriptor format sense data, the current state of all TapeAlert flags appears in the Information sense data descriptor. If not, the drive returns fixed format sense data and the application should read one of the TapeAlert log pages to retrieve the state of the TapeAlert flags.

For more information see SSC-3 rev 02, section 4.2.15.

Reading the TapeAlert log

Each time the TapeAlert log page is read, the application should follow this procedure:

1.Read all 64 flags to discover which are set (there may be more than one).

There may also be data associated with a set flag in the remainder of the flag byte, which should also be read.

2.For each flag that is set, log the associated error message.

3.Notify the user through the normal methods (such as broadcast, E-Mail, SNMP) by displaying the error message suggested in the table. Include the following:

•Details to identify which drive the message refers to.

•The software label of the tape cartridge when relevant.

•The severity of the message (Information, Warning or Critical, with Critical the most severe). Where there are several flags set, list the messages in ascending order of severity.

4.Apply any error message filters in the software to the TapeAlert errors. If several TapeAlert flags are set, they should if possible be presented to the user as a single event. For example, the error messages could be displayed together in a single message box.

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Contents volume 2 software integration LTO 4 FC, SCSI and SAS drivesHP LTO Ultrium tape drives technical reference manual HP restrictedLegal and notice information Contents 1 Designing backup applications2 Configuration and initialization 3 Use of tapes5 Supporting Ultrium features 4 Factors affecting performance6 Sense keys and codes 7 Exception handlingHP restricted Related documents Documentation mapDocuments specific to HP Ultrium drives Drives-generalInstallation and configuration OperationCartridges InterfaceMaintenance and troubleshooting Dealing with errorsLTO Ultrium features General documents and standardization1 Designing backup applications Non-immediate commandsOptimizing performance Large data transfer sizeCleaning tape heads Managing the use of tapesInformation in Cartridge Memory Monitoring tape useDesign goals for LTO backup applications Diagnostic logsTapeAlert Displaying drive informationInclude the capability to download firmware Inquiry string recovery 2 Configuration and initializationOperating system drivers 16 Configuration and initialization ExampleSCSI protocol, regardless of transport or interface type Enabling additional LUN support Support for additional LUNSupporting additional LUNs 18 Configuration and initialization Using Cartridge Memory attributes Using MODE SENSE3 Use of tapes LTO cartridge memoryFinding the remaining capacity Tape status and capacityInterpreting Log Sense data Command descriptor block Using the SET CAPACITY commandCDB fields Changes to SCSI commands WORM mediaHow WORM media works New additional sense codes and TapeAlert flagsError Usage page ERASE commands rejectedSET CAPACITY command Re-writing media labelsBehavior with a missing or inconsistent EOD value Using CM to check tape integrityUnique media identifier Load count Responding to Cartridge Memory dataBarcode support RWW retry counts Corrective action4 Factors affecting performance Ways of optimizing performanceDetecting the drive’s speed Ensuring the recommended minimum transfer sizesUsing Cartridge Memory instead of tape headers Using the Performance Log page for diagnosing problemsTime-out values Media type identificationFactors affecting performance Recommended support of log pagesHost-related factors Example Recommendationwhere possible or a reasonably sized RAID system. More disks means 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 5 Supporting Ultrium features Cartridge Memory LTO-CMAutomation interface Further informationAutomation/Device Interface ADI Modes of usage through ACI Automation Control Interface ACISlave to a library controller ACI commands that affect drive streaming performance ACI command setSCSI pass-through mode New features in ACI Backward compatibilitySCSI command Encryption support Further details Supporting the ACI protocolRecommended ACI time-out values 42 Supporting Ultrium featuresRecommended power-up sequence Treatment of reserved fieldsRecommended load-unload configuration Firmware upgrade via tape Recommended Get Drive Status polling frequencyACI protocol communications retry Upgrading the drive firmwareFirmware upgrade via the primary host interface Firmware upgrade via ACILibrary firmware upgrade via tape Handling irregular cartridgesCleaning cartridge HP-configured or Universal Expired cleaning cartridge HP-configured or UniversalNon-HP Ultrium 1 cleaning cartridge Unreadable data cartridgeValid firmware upgrade cartridge Data cartridge with unreadable CMCartridge fails to seat or load Cartridge cannot be loadedFrequently 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 lineAccessing Cartridge Memory without threading the tape Controlling data compressionOther mode page information Buffer size at EW-EOMRewind on reset Write delay timePartition size 52 Supporting Ultrium features6 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 applicationAction Console MessageAction Console Messagepage Additional sense codes-actions to take PhysicalEnd-of-Tape reached, unable to fit0h-NO SENSE 1h-RECOVERED ERROR 2h-NOT READYThe software must issue a LOAD before media access LUN not accessible, port inThe command cannot be executed because the specified 60 Sense keys and codesmechanism tests are being executed. When the tests are A READ , SPACE , WRITE or WRITE FILEMARKS command 3h-MEDIUM ERROR62 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 A MODE SELECT parameter list sent to the drive contains 5h-ILLEGAL REQUEST68 Sense keys and codes 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 OUTAction 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 successful7h-DATA PROTECTION Code 8h-BLANK CHECK READ BUFFER command Bh-ABORTED COMMANDrelated to a missing EOD data set. The most likely cause A WRITE or WRITE FILEMARKS command has encountered Dh-VOLUME OVERFLOW76 Sense keys and codes Typical escalation procedure 1. Retrieve fault information3. Allow the user to try recovery 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 modelsTapeAlert polling usage model Reading the TapeAlert logTapeAlert informational exception usage model Responding to the ‘Clean’ LED One-Button Disaster Recovery OBDRSupporting 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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