Promise Technology TX4, TX8 user manual RAID 5 Block and Parity Striping

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RAID 5 – BLOCK AND PARITY STRIPING

RAID 5 is similar to RAID 3 as described above except that the parity data is rotated across the physical drives along with the block data. Having the parity data striped across all the physical drives in this manner removes the random write performance bottleneck of RAID 3. The total capacity of a RAID 5 array is calculated the same as a RAID 3 array.

Figure A5. RAID 5 stripes all drives with data and parity information

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Contents ULTRATRAK100 TX4 ULTRATRAK100 TX8 Copyright TrademarksImportant Data Protection Information Radio Frequency Interference Statement Table of Contents RAID Page Architectural Description IntroductionFeature Benefit Features and BenefitsUnpack ULTRATRAK100 Install Hard DrivesConfiguration Getting StartedUltraTrak100 Disk Drive Access TX4 Shown Back of UltraTrak100 TX4 see for TX8 Connecting the Scsi CablesDaisy Chaining Several UltraTrak100s Together Assign a Scsi ID Connect Power Cable and Switch Power onConfigure the ULTRATRAK100 Press SEL to Save Changes Advantages Disadvantages Choosing a RAID LevelRAID 0+1 Characteristics/Advantages DisadvantagesJbod Partition and Format the ArrayCritical & Offline Arrays MaintenanceDrive Status Indicators Indicator Color MeaningREBUILDING/SYNCHRONIZING Fault Tolerant Arrays When a Disk Drive FailsReplacing a Disk Drive Module Drive Carrier Drive ReplacementReplacing a Power Supply Module TX8 only Connecting Cables to Disk DriveBack of UltraTrak100 TX8 Type of Interface Name Comments ULTRATRAK100 Front Panel InterfaceArray Functional Error ModeConfiguration Mode LCD MessagesView Status Configure Array Configure Cache Configure ScsiView Status View Enclosure View Controller InfoView Cache Stats View Array InformationView Controller Information 5009 RPM Temperature 30C/86FArray 0 Size 12GB RAID 0 FunctionalCreate/Cancel Delete Array Auto Array SetupPress SEL to Create Press Exit to Cancel What you can do View Drive Assignments Define ArrayMaxtor Asng In Ary IBM Asng In Ary No Free Disk What you can doRAID Level 4KB 8KB IBM Assigned Maxtor Free Maxtor FreeWipe out disk Synchronize Array Disable Buzzer Rebuild/Sync Pri. Low Array IDWrite Back Write CacheWrite Cache What you can do Write Back Write Thru What you can doID Selected ModePress Or to move these items on the LCD What you can do Scsi IDEuropean Tech Support Technical Support ServicesContacting Promise Support USA Tech Support CenterChina Office Pacific Rim Sales OfficeDisclaimer of Other Warranties Limited WarrantyPage Returning Product for Repair USA & Canada Your Responsibilities Introduction to RAID Appendix a Technology BackgroundRAID 1 Mirroring RAID 0+1 STRIPING/MIRROR RAID 3 Block Striping with Parity Drive RAID 5 Block and Parity Striping Jbod Spanning Appendix B Frequently Asked Questions Why can’t I see the drives on the UltraTrak100 under FDISK?