HP LTO 4 SCSI, LTO 4 FC, LTO 4 SAS Automation Control Interface ACI, Modes of usage through ACI

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Automation Control Interface (ACI)

Automation Control Interface (ACI)

The Automation Control Interface (ACI) protocol allows the activities of the drive to be coordinated within a library. The protocol has been designed so that it can be made into a standard feature of tape drives. It provides a rich and extensible functionality to allow automation manufactures to add value in their application of it.

The interface is a serial bus with additional control lines, designed to connect the Ultrium tape drive to an automation controller in a tape library. Each tape drive position has a separate ACI connection allowing communication to the drive via its RS 422 serial port.

The ACI protocol provides the following fundamental functions:

•Coordinating the automation controller and the tape drive for Load and Unload operations

•Allowing the automation controller to retrieve information from the tape drive

•Setting tape drive configuration information

In addition, the following functions may be supported depending on the way that the tape library is configured:

•Providing upload and download of firmware images

•Providing access to Cartridge Memory contents

•Providing a protocol for passing SCSI commands to the tape drive over the interface.

The ACI protocol allows for “packetized” SCSI commands to be sent from the attached controller and submitted to the tape drive as if they have been received on the drive’s own SCSI bus. For example, the ACI protocol allows the sending of load/unload commands from a specially defined automation command set to cause drive action. This ability enables the attached controller to access and control the drive in exactly the same way as it would over the SCSI bus.

Modes of usage through ACI NOTE: Ultrium SCSI Parallel drives implement a limited subset of the SCSI commands, including INQUIRY, LOG SENSE, LOG SELECT and MODE SENSE.

The following notes should be regarded as supplementing the ACI protocol specification rather than replacing them. Please refer to the specification for further implementation details. These notes refer to the “standard” automation drive variant. Different behavior may be exhibited in certain areas for specific OEM variants as requested by OEMs.

Modes of usage through ACI

Slave to a library controller

The ACI can receive commands such as LOAD and UNLOAD from a specially defined automation command set to control the action of the drive.

Most tape libraries need to have a means of communication between controller and tape drives, to enable correct synchronization of mechanical operations between drive and picker arm. For instance, in a soft load capable device such as an Ultrium drive, the picker must let go of the

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Contents LTO 4 FC, SCSI and SAS drives volume 2 software integrationHP LTO Ultrium tape drives technical reference manual HP restrictedLegal and notice information 1 Designing backup applications Contents2 Configuration and initialization 3 Use of tapes4 Factors affecting performance 5 Supporting Ultrium features7 Exception handling 6 Sense keys and codesHP restricted Documentation map Related documentsDocuments specific to HP Ultrium drives Drives-generalOperation Installation and configurationCartridges InterfaceDealing with errors Maintenance and troubleshootingGeneral documents and standardization LTO Ultrium featuresNon-immediate commands 1 Designing backup applicationsOptimizing performance Large data transfer sizeManaging the use of tapes Cleaning tape headsInformation in Cartridge Memory Monitoring tape useDiagnostic logs Design goals for LTO backup applicationsTapeAlert 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 MODE SENSE Using Cartridge Memory attributes3 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 WORM media Changes to SCSI commandsHow WORM media works New additional sense codes and TapeAlert flagsERASE commands rejected Error Usage pageSET 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 Corrective action RWW retry countsWays of optimizing performance 4 Factors affecting performanceDetecting the drive’s speed Ensuring the recommended minimum transfer sizesUsing the Performance Log page for diagnosing problems Using Cartridge Memory instead of tape headersTime-out values Media type identificationFactors affecting performance Recommended support of log pagesHost-related factors Recommendation Examplewhere possible or a reasonably sized RAID system. More disks means makes sense to split heavily used FC cards across separate PCI bussesDo not interleave write commands with other commands, such as READ Drive-related factorsFormat-related factors Page 34 Factors affecting performance Cartridge Memory LTO-CM 5 Supporting Ultrium featuresAutomation 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 Backward compatibility New features in ACISCSI command Encryption support Supporting the ACI protocol Further detailsRecommended ACI time-out values 42 Supporting Ultrium featuresTreatment of reserved fields Recommended power-up sequenceRecommended load-unload configuration Recommended Get Drive Status polling frequency Firmware upgrade via tapeACI protocol communications retry Upgrading the drive firmwareFirmware upgrade via ACI Firmware upgrade via the primary host interfaceLibrary firmware upgrade via tape Handling irregular cartridgesExpired cleaning cartridge HP-configured or Universal Cleaning cartridge HP-configured or UniversalNon-HP Ultrium 1 cleaning cartridge Unreadable data cartridgeData cartridge with unreadable CM Valid firmware upgrade cartridgeCartridge fails to seat or load Cartridge cannot be loadedCleaning Frequently asked questionsInvalid firmware upgrade cartridge Is there separate firmware for drives intended to go into libraries?Resetting drives Backup softwareResetting via the ACI Reset command Resetting using the ACIRSTL lineControlling data compression Accessing Cartridge Memory without threading the tapeOther mode page information Buffer size at EW-EOMWrite delay time Rewind on resetPartition size 52 Supporting Ultrium featuresSense keys-actions to take 6 Sense keys and codesAction Console MessageFor additional sense codes, see “3h-MEDIUM ERROR” on “3h-MEDIUM ERROR” on page 62 . Also see the Media Accesslog the error, terminate I/O to the drive, and pass the appropriate error to the calling applicationConsole Message ActionAction Console MessageAction Physical Additional sense codes-actions to takeEnd-of-Tape reached, unable to fit0h-NO SENSE 2h-NOT READY 1h-RECOVERED ERRORLUN not accessible, port in The software must issue a LOAD before media accessThe 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 and the drive. Based on this, ask the user to clean the Send a console message that an unrecovered error on64 Sense keys and codes Send a message to the console indicating that there is 66 Sense keys and codes The current command such as READ, SPACE, REWIND4h-HW ERROR A MODE SELECT parameter list sent to the drive contains 5h-ILLEGAL REQUEST68 Sense keys and codes persistent reservation using the PERSISTENT RESERVE OUT 6h-UNIT ATTENTIONallowed to execute. In other words, some commands can 32 initiators to register, using PERSISTENT RESERVE OUTAction A PERSISTENT RESERVE OUT command was executed service action removed all reservations and the persistentWRITE BUFFER or MAINTENANCE OUT command A SET DEVICE IDENTIFIER command has been successful7h-DATA PROTECTION Action 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 1. Retrieve fault information Typical escalation procedure3. Allow the user to try recovery 4. Allow the user to reset devicesSupporting TapeAlert Monitoring the condition of the drive and mediaType FlagsPage Page Page Page Page Page Page TapeAlert models Designing software to use the TapeAlert logTapeAlert polling usage model Reading the TapeAlert logTapeAlert informational exception usage model Responding to the ‘Clean’ LED One-Button Disaster Recovery OBDRSupporting OBDR Requirements for drivers and logical device managers Providing pass-through modeGlossary see ”read-while-write” Index Page Page HP restricted
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