Dell H200 manual About RAID, RAID Terminology, RAID Levels

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About RAID

RAID is a group of multiple independent physical disks that provide high performance or better data availability by increasing the number of drives used for saving and accessing data. A RAID disk subsystem improves

I/O performance and data availability. The physical disk group appears to the host system as a single storage unit. Data throughput improves because multiple disks can be accessed simultaneously. RAID systems also improve data storage availability and fault tolerance.

RAID Levels

RAID 0 uses disk striping to provide high data throughput, especially for large files in an environment that requires no data redundancy.

RAID 1 uses disk mirroring so that data written to one physical disk is simultaneously written to another physical disk. This is good for small databases or other applications that require small capacity, but complete data redundancy.

RAID 10, a combination of RAID 0 and RAID 1, uses disk striping across mirrored disks. It provides high data throughput and complete data redundancy.

CAUTION: Lost data on a RAID 0 disk cannot be recovered in the event of a physical disk failure.

RAID Terminology

RAID 0

RAID 0 allows you to write data across multiple physical disks instead of just one physical disk. RAID 0 involves partitioning each physical disk storage space into 64 KB stripes. These stripes are interleaved in a repeated sequential manner. The part of the stripe on a single physical disk is called a stripe element.

For example, in a four-disk system using only RAID 0, segment 1 is written to disk 1, segment 2 is written to disk 2, and so on. RAID 0 enhances performance because multiple physical disks are accessed simultaneously, but it does not provide data redundancy. Figure 2-2 shows an example of RAID 0.

Overview

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Contents User’s Guide July Contents Installing the RPM Package With Installing the Perc H200 and 6GbpsInstalling a Windows Server 2003, Windows Installing Suse Linux Enterprise ServerMigrating and Activating a Virtual Disk Bios Fault Code Messages Booting With Multiple ControllersStarting the Configuration Utility Assigning a Preferred Boot Device ContentsFirmware Package Update Utility Technical Support and Customer ServiceAutomated Order-Status Service Corporate Contact Details Contents Safety General Page Safety Battery Disposal Page Overview OverviewGbps SAS HBA Hardware Architecture Operating System SupportAbout RAID RAID TerminologyRAID Levels Example of RAID Stripe element Stripe element 1 duplicated Overview Perc H200 and 6Gbps SAS HBA Features Specifications of Perc H200Perc H200 and 6Gbps SAS HBA Features RAID 0, RAID Specifications of 6Gbps SAS HBA Lists the specifications of the 6Gbps SAS HBALater 64-bit only LED Port Activity Feature for 6Gbps SAS HBA Only Unsupported Drives Physical Disk Cache PolicyHardware Installation Installing the Perc H200 and 6Gbps SAS HBA CardsHardware Installation SAS HBA Connecting the Cable for Perc H200 Connecting the Cable for 6Gbps SAS HBA Installing the Perc H200 Modular Card To install your new storage controller card Driver Installation Driver InstallationInstalling the Windows Driver Pre-Installation RequirementsCreating the Driver Media Boot the system using the Windows Server 2003 media Driver Installation Locate Driver Files screen Follow the step below according to your operating system Updating the Windows DriverCreating a DUD Installing Linux DriverUnzip the package using gunzip Untar the file using tar -xvf Creating a DUD Using Dkms Installing Suse Linux Enterprise Server Using the DUD Upgrading the Kernel Installing the RPM Package With Dkms SupportDriver Installation Post Messages Perc H200 and 6Gbps SAS HBA BiosBios Fault Code Messages Perc H200 and 6Gbps SAS HBA BiosFunctions Performed Configuration UtilityBooting With Multiple Controllers Starting the Configuration UtilityFunctions of the Configuration Utility Description RAID Configuration and Management Screens Select New Volume Type Create New VolumeVolume Field Descriptions RAID Volume Field Descriptions Assign a hot spare, RAID 1 and RAID 10 configurations only View VolumeManage Volume Manage Volume Field DescriptionsExit Screen Performing Configuration TasksCreating a RAID 0 Virtual Disk Creating a RAID 1 Virtual Disk Creating a RAID 10 Virtual Disk Perc H200 and 6Gbps SAS HBA Bios Activating a Virtual Disk Viewing Virtual Disk PropertiesDeleting a Virtual Disk Migrating and Activating a Virtual DiskReplacing and Rebuilding a Degraded Virtual Disk Hot Spare FailoverAssigning a Preferred Boot Device Current Boot Device set to volume at handle Background Activities TroubleshootingBios Boot Order TroubleshootingGeneral Issues Physical Disk Related Issues Configuration Utility Error Messages Configuration UtilityFor Configuration Utility Bios Error Messages Meaning Bios Error MessagesBios Error Messages MessageMeaning Bios Fault 01 No I/O port assigned to the adapter Message indicates that the preferred boot Troubleshooting Firmware Package Update Utility Updating the FirmwareAppendix a Updating the Firmware Appendix a Updating the Firmware Technical Support and Customer Service Getting HelpAppendix B Getting Help Online Services Dell Enterprise Training Problems With Your Order Automated Order-Status ServiceProduct Information Before You Call Returning Items for Warranty Repair or CreditAppendix C Regulatory Notices Regulatory NoticesAppendix C Regulatory Notices Appendix D Corporate Contact Details Taiwan Only Corporate Contact Details Taiwan OnlyAppendix D Corporate Contact Details Taiwan Only Glossary GlossaryDkms Glossary Operating System PHY RAID Sata Smart Page Glossary Index IndexIndex