HP Microsoft Windows Server 2003 for Itanium-based Systems RAID 0-No fault tolerance, Advantages

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•RAID 1+0—Drive Mirroring

•RAID 5—Distributed Data Guarding

•RAID 6 (ADG)—Advanced Data Guarding

RAID 0—No fault tolerance

A RAID 0 configuration provides data striping, but there is no protection against data loss when a drive fails. However, it is useful for rapid storage of large amounts of noncritical data (for printing or image editing, for example) or when cost is the most important consideration.

Advantages:

•Has the highest write performance of all RAID methods.

•Has the lowest cost per unit of stored data of all RAID methods.

•All drive capacity is used to store data (none is needed for fault tolerance).

Disadvantages:

•All data on the logical drive is lost if a physical drive fails.

•Cannot use an online spare.

•Can only preserve data by backing it up to external drives.

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Contents HP Array Configuration Utility User Guide Audience assumptions Contents Diagnosing array problems Installing ACU Features and system requirementsGetting started This sectionSetting the execution mode for Microsoft Windows Overview for using ACUComparison of ACU execution modes Choosing an operating mode Opening ACU in Local Application modeHttp//servername2301 Opening ACU in Browser modeSelect Device Queries Opening ACU through Systems Insight ManagerGUI operating modes Typical Standard mode screenTypical Configuration Wizards mode screen Typical Express Configuration mode screen Completing the configuration processUsing Standard Configuration mode Configuring a new controllerPossible tasks in Standard Configuration mode Using Express Configuration mode Creating an array Using the configuration wizardsClick Finish Click Create an array, and then click BeginConfiguring a new controller Click Create a logical drive, and then click Begin Creating a logical driveConfiguring a new controller Modifying a configuration using Standard Configuration mode Modifying an existing configurationChoices available after opening ACU Modifying a configuration using the Configuration wizards Modifying a configuration using Express modeClear Configuration Click Express Configuration, and then click BeginClick Controller Settings, and then click Begin Controller settingsCreate an array Create a logical drive Delete arrays Expand Array Delete logical drivesClick Delete logical drives, and then click Begin Migrate a logical drive Extend logical driveClick Extend logical drive, and then click Begin Click Migrate a logical drive, and then click BeginSelective Storage Presentation Spare managementRA4x00 controllers Click Spare Management, and then click BeginMSA and Smart Array Cluster storage controllers Click ACU Switch Configuration Configuring switchesRecombining a split, mirrored array Splitting a mirrored arrayModifying an existing configuration Scripting in ACU Command line syntaxIntroduction to scripting in ACU Operating modesCpqacuxe -i Filename Sample custom input scriptDescription of option categories in ACU scripting Script file optionsController category Control categoryAction MethodController ClearConfigurationWithDataLossLicenseKey, DeleteLicenseKey RAIDArrayIDArray category SurfaceScanDelayRebuildPriority, ExpandPriority SSPStateOnlineSpare Logical Drive categoryDrive LogicalDriveSectors SizeStripeSize ArrayAcceleratorSSPAdaptersWithAccess Error reportingConnectionName HostModeACU scripting error messages 0-9, !, @, #, *, , , ,, -, , +, , ., /, and space. The ID Current configuration Overview of the ACU CLI Using the Command Line InterfaceRunning the CLI CLI syntax Command variableKeyword abbreviations Target variableExample command Typical proceduresHiding warning prompts Querying a deviceSyntax Sample scenarioModifying the controller chassis name Example commandsExample Sample scenario Using Selective Storage PresentationManaging host modes connection profiles Modifying connection namesIdentifying devices Deleting target devicesExpanding an array Extending a logical driveManaging spare drives Target modify raid=01+0156adg? ss=8163264128256default?Migrating a logical drive Target modify size=#max? forcedChanging the Expand Priority setting Changing the Rebuild Priority settingChanging the controller cache ratio Re-enabling a failed logical drive Changing the surface scan delay timeEnabling or disabling the drive cache Enabling or disabling the array accelerator Setting the targetDisabling a redundant controller Typical scenario= rescan Rescanning the systemFactors involved in logical drive failure Probability of logical drive failureProbability of logical drive failure Drive arrays Drive arrays and fault-tolerance methodsDrive arrays and fault-tolerance methods Hardware-based fault-tolerance methods Fault-tolerance methodsAdvantages RAID 0-No fault toleranceDisadvantages RAID 1+0-drive mirroring RAID 6 ADG-Advanced Data Guarding RAID 5-distributed data guardingRAID RAID 6 ADG Comparing the hardware-based RAID methodsSelecting a RAID method Alternative fault-tolerance methodsDiagnostic tools Diagnosing array problemsServer Diagnostics Post messagesAcronyms and abbreviations SSP Index Index