Dell EMC H740P User Manual Download Page 1

Dell EMC PowerEdge RAID Controller 10 User’s 
Guide

H740P, H745P MX, and H840

Regulatory Model: UCPA-1001, UCPB-1000, UCPE-1000 and UCPJ-1000

Summary of Contents for H740P

Page 1: ...Dell EMC PowerEdge RAID Controller 10 User s Guide H740P H745P MX and H840 Regulatory Model UCPA 1001 UCPB 1000 UCPE 1000 and UCPJ 1000 ...

Page 2: ...age to hardware or loss of data and tells you how to avoid the problem WARNING A WARNING indicates a potential for property damage personal injury or death 2017 2018 Dell Inc or its subsidiaries All rights reserved Dell EMC and other trademarks are trademarks of Dell Inc or its subsidiaries Other trademarks may be trademarks of their respective owners 2018 11 Rev A03 ...

Page 3: ...H745P MX enclosure support 15 PERC H840 enclosure support 17 Profile Management 19 Virtual disk features 19 Virtual disk write cache policies 20 Virtual disk read cache policies 20 Virtual disk migration 21 Virtual disk initialization 21 Reconfiguration of virtual disks 22 Background operations 24 Hard drive features 24 Self Encrypting Disks 24 Instant Secure Erase 25 4 KB sector disk drives 25 Fa...

Page 4: ...dows Server 2012 R2 and newer installation 38 Updating PERC 10 driver for existing Windows Server 2012 R2 and newer 39 Linux driver installation 39 Installing or updating the RPM driver package with KMOD support 40 Installing or updating the RPM driver package with KMP support 40 Loading the driver during operating system installation 40 6 Firmware 42 Installing the firmware using DUP 42 7 HII con...

Page 5: ... Convert to Non RAID disk 59 Hardware components 60 Viewing battery properties 60 Viewing physical disks associated with an enclosure 60 8 Security key and RAID management 61 Security key implementation 61 Security key management in the HII configuration utility 61 Local Key Management 61 Creating security key 62 Changing Security Settings 62 Disabling security key 62 Creating secured virtual disk...

Page 6: ...ual disk fails during rebuild using a global hot spare 70 Virtual disk fails during rebuild using a dedicated hot spare 70 Physical disk fails during reconstruction on redundant virtual disk 70 Virtual disk fails rebuild using a dedicated hot spare 70 Physical disk takes a long time to rebuild 71 SMART errors 71 Smart error detected on a physical disk in a redundant virtual disk 71 Smart error det...

Page 7: ...11 Getting help 78 Contacting Dell EMC 78 Documentation feedback 78 Contents 7 ...

Page 8: ... control capabilities which include support for RAID levels 0 1 5 6 10 50 and 60 Provides reliability high performance and fault tolerant disk subsystem management Topics Supported operating systems PERC card specifications Management applications for PERC cards Related documentation Supported operating systems The PERC 10 series cards support the following operating systems NOTE For more informat...

Page 9: ...240 Maximum number of disks Enhanced HBA mode 240 combination of virtual disks and Non Raid disks 240 combination of virtual disks and Non Raid disks N A Maximum number of virtual disks per disk group 16 16 16 Hot swap devices supported Yes Yes Yes Hardware XOR Engine Yes Yes Yes Online capacity expansion Yes Yes Yes Dedicated and global hot spare Yes Yes Yes Drives Types 3 Gbps SATA 6 Gbps SATA S...

Page 10: ...ion for Dell systems that provides enhanced features for configuring a system s locally attached RAID disk storage The Dell OpenManage storage management application enables you to perform controller and enclosure functions for all supported RAID controllers and enclosures from a single graphical or command line interface The graphical user interface GUI is wizard driven with features for novice a...

Page 11: ...on card consisting of 8 GB Non Volatile Cache and is available in the Adapter low profile and full height and Mini Monolithic form factors for internal storage Figure 1 Features of PERC H740P adapter 1 heat sink 2 battery 3 battery cable 4 battery cable connector 5 port B 6 port A Figure 2 Features of PERC H740P mini monolithic card 1 heat sink 2 battery 2 Getting Started 11 ...

Page 12: ...zanine connector 2 release lever 3 heat sink 4 SAS cable connector 5 battery cable connector 6 battery PERC H840 The PERC H840 is similar to the H740P solution except that it supports external storage The PERC H840 is only available in the Adapter low profile and full height form factor Figure 4 Features of PERC H840 adapter card 1 heat sink 2 battery 3 battery cable 4 battery cable connector 5 po...

Page 13: ...ite IO size and RAID type Disk roaming Disk roaming is moving the physical disks from one cable connection or backplane slot to another on the same controller The controller automatically recognizes the relocated physical disks and logically places them in the virtual disks that are part of the disk group You can perform disk roaming only when the system is turned off CAUTION Do not attempt disk r...

Page 14: ...irmware update This feature provides a cryptographic method of updating the firmware using RSA encryption decryption algorithm Only Dell certified firmware is supported on your PERC controller Enhanced HBA mode Enhanced HBA mode eHBA mode is a new operating mode available with H740P and H745P MX cards eHBA provides the following features Create virtual disks with RAID level 0 1 or 10 Present Non R...

Page 15: ...e host and not a RAID volume The only supported cache policy for Non RAID disks is write through Auto Configure RAID 0 Auto Configure RAID 0 feature creates a single drive RAID 0 on each physical disk that is in the ready state For more information see Auto Configure RAID 0 PERC H745P MX enclosure support The H745P MX is a RAID controller for the PowerEdge MX740c and MX840c compute sleds It is use...

Page 16: ... the Dell com openmanagemanuals OpenManage Enterprise Modular NOTE The I O modules cannot be configured independently The H745P MX is connected to the SAS IOM which in turn connects to one of the SAS expanders in the storage sled The expander in the storage sled is then connected to all the physical drives in the storage sled providing one path between the H745P MX and a physical drive in the stor...

Page 17: ...t paths when used with Dell PowerVault MD14XX series disk storage enclosures NOTE The Enhanced HBA mode is not supported on PERC H840 Figure 6 PERC H840 card ports Four enclosures with multipath configuration To set up an enclosure on the PERC H840 card a To connect multiple enclosures two cables connect the first enclosure to the second enclosure then two more cables connect the second enclosure ...

Page 18: ...sure Management Module EMM by utilizing the remaining path When redundant paths exist the controller automatically balances I O load through both paths to each disk Load balancing increases throughput to virtual disks in storage enclosures and is automatically turned on when redundant paths are detected To set up your hardware to support redundant paths see Setting up redundant path support on the...

Page 19: ...rmation see Changing profile using HII Configuration Utility NOTE When H740 or H840 controller is upgraded to 50 3 0 1022 from an older firmware profile on the controller is set to PD64 Table 3 Supported Profiles on PERC 10 Feature PD64 PD240 Profile ID 10 12 Maximum physical disk supported 64 240 Maximum virtual disk supported 64 240 Controller queue depth 4096 3072 Maximum enclosure supported On...

Page 20: ...y of the virtual disk The PERC cards manage the data in cache independently of the operating system or any applications NOTE Certain data patterns and configurations perform better with a Write Through cache policy NOTE Use the Dell OpenManage storage management application or the HII Configuration Utility to view and manage virtual disk cache settings Conditions under which write back is employed...

Page 21: ...0P and H810 to PERC10 series NOTE The source controller must be offline prior to performing the disk migration NOTE Importing non RAID drives and uneven span RAID 10 virtual disks from PERC 9 to PERC 10 are not supported NOTE Disks cannot be migrated to older generations of the PERC cards NOTE Importing secured virtual disks is supported as long as the appropriate Local Key Management LKM is suppl...

Page 22: ...ual disks exist within a common disk group those virtual disk s capacities cannot be expanded 2 Free space is also available when a disk group s physical disks are replaced by larger disks using the Replace Member feature A virtual disk s capacity can also be expanded by performing an OCE operation to add more physical disks RAID Level Migration RLM refers to changing a virtual disk s RAID level B...

Page 23: ... disk and reclaims disk space used for distributed parity data RAID 5 RAID 5 3 or more 4 or more Yes Increases capacity by adding disks RAID 5 RAID 6 3 or more 4 or more Yes At least one disk needs to be added for dual distributed parity data RAID 6 RAID 0 4 or more 4 or more Yes Converts to a non redundant virtual disk and reclaims disk space used for distributed parity data RAID 6 RAID 5 4 or mo...

Page 24: ...ing the HII Configuration Utility or the Dell OpenManage storage management application You can schedule a CC to run on virtual disks using the Dell OpenManage storage management application To start a CC using the HII Configuration Utility see Performing consistency check NOTE CC BGI typically causes some loss in performance until the operation completes Consistency Check CC and BGI both correct ...

Page 25: ...ring and Reporting Technology SMART Patrol Read Physical disk failure detection Physical disk rebuild using hot spares Controller cache preservation Battery and non volatile cache backup of controller cache to protect data Detection of batteries with low charge after boot up The next sections describe some methods to achieve fault tolerance The SMART feature The SMART feature monitors certain phys...

Page 26: ...sks on the controller that are configured as part of a virtual disk including hot spares Patrol Read does not run on physical disks that are not part of a virtual disk or are in Ready state Patrol Read adjusts the amount of controller resources dedicated to Patrol Read operations based on outstanding disk I O For example if the system is busy processing I O operation then Patrol Read uses fewer re...

Page 27: ...irtual disk is optimal After the failed disk is replaced in the same slot and the rebuild to the hot spare is complete the controller automatically starts to copy data from the commissioned hot spare to the newly inserted disk After the data is copied the new disk is a part of the virtual disk and the hot spare is reverted to being a ready hot spare This allows hot spares to remain in specific enc...

Page 28: ...city once every 90 days The operation can be performed manually if required NOTE Virtual disks stay in Write Back mode if enabled during transparent learn cycle When the TLC completes the controller sets the next TLC to 90 days Transparent Learn Cycle Completion Time The time frame for completion of a learn cycle is a function of the battery charge capacity and the discharge and charge currents us...

Page 29: ...irected by the online or telephone service and support team Damage due to servicing that is not authorized by Dell is not covered by your warranty Read and follow the safety instructions that are shipped with your product NOTE It is recommended that you always use a static mat and static strap while working on components in the interior of the system CAUTION To prevent damage to the card you must ...

Page 30: ...he interior of the system 1 Turn off the system including any attached peripherals and disconnect the system from the electrical outlet 2 Open the system 3 Align the card edge connector with the connector on the system board To prevent damage to the card you must hold the card by its edges only 4 Press the card edge down until the card is fully seated 5 Connect the SAS data cable connectors to the...

Page 31: ...terior of the system CAUTION To prevent damage to the card you must hold the card by its edges only 1 Turn off the system including any attached peripherals and disconnect the system from the electrical outlet and peripherals 2 Open the system 3 Locate the PERC card on the system board 4 Using 2 Philips screw driver loosen the screws that secure the controller cable to the card connector on the sy...

Page 32: ... NOTE It is recommended that you always use a static mat and static strap while working on components in the interior of the system 1 Turn off the system including any attached peripherals and disconnect the system from the electrical outlet 2 Open the system 3 Align the end of the card with the card connector on the system board and the other end of the card at an angle with the plastic bracket o...

Page 33: ...nt damage to the card you must hold the card by its edges only 1 Turn off the sled including any attached peripherals and remove the sled from the MX chassis NOTE Perform a graceful shutdown of the sled to ensure any data in the cache is flushed to the disk before the controller is removed 2 Open the sled 3 Locate the PERC card on the system board 4 Using the blue tab rotate the lever of the contr...

Page 34: ...recommended that you always use a static mat and static strap while working on components in the interior of the system 1 Turn off the sled and any attached peripherals and remove the sled from the MX chassis 2 Open the sled 3 Connect the SAS backplane data cable connector to the card NOTE Ensure that you connect the cable according to the connector labels on the cable The cable does not function ...

Page 35: ...ou always use a static mat and static strap while working on components in the interior of the system CAUTION To prevent damage to the card you must hold the card by its edges only 1 Turn off the system including any attached peripherals and disconnect the system from the electrical outlet and peripherals 2 Open the system 3 Locate the PERC card on the system board 4 Disconnect the SAS cables conn...

Page 36: ...le does not function properly if reversed 6 Close the system 7 Reconnect the system to its electrical outlet and turn on the system and any attached peripherals Part replacement of a PERC card in eHBA mode When replacing a PERC card verify the controller mode of operation after replacing the card If a controller mode change is still necessary you may request the desired mode and reboot Before chan...

Page 37: ...ing the driver during a Windows Server 2012 R2 and newer installation Installing the driver after Windows Server 2012 R2 and newer installation Updating PERC 10 driver for existing Windows Server 2012 R2 and newer Linux driver installation Creating the device driver media Use one of the following two methods to create the device driver media Downloading Drivers From The Dell Support Website Downlo...

Page 38: ...wnload the latest BIOS firmware and driver updates from Dell com support Create a device driver media using one of the methods listed below USB drive CD DVD Installing the driver during a Windows Server 2012 R2 and newer installation To install the driver 1 Boot the system using the Windows Server 2012 R2 or newer media 2 Follow the on screen instructions until you reach Where do you want to insta...

Page 39: ...ontrollers 6 Double click the RAID controller for which you want to update the driver 7 Click the Driver tab and click Update Driver The screen to update the device driver wizard is displayed 8 Select Install from a list or specific location 9 Click Next 10 Follow the steps in the wizard and browse to the location of the driver files 11 Select the INF file from the driver media CD DVD or other med...

Page 40: ...on rpm NOTE Use rpm Uvh package name when updating an existing package 3 If the previous device driver is in use you must reboot the system for the updated driver to take effect 4 Verify that the driver is loaded with the following system commands modinfo megaraid_sas Loading the driver during operating system installation 1 Navigate to the installer 2 In the Installation screen press E 3 Perform ...

Page 41: ...NOTE Ensure that you disconnect the driver media so that the drivers are loaded successfully 9 Press C or exit to continue with the installation Driver installation 41 ...

Page 42: ...E For VMware firmware should be updated through iDRAC or the PERC CLI utlitily 4 Install the DUP a For Windows run the executable in Windows environment b For Linux run bin file in Linux environment c For iDRAC navigate to system iDRAC Maintenance System Update upload Windows executable and then install NOTE Firmware downgrade from 50 3 0 1022 or later to the older version is not supported via DUP...

Page 43: ...ontroller use the arrow keys or the mouse NOTE For more information in all the options click Help that is available on the top right hand corner of the browser screen Help information for individual option menus can also be viewed by scrolling down on each option NOTE Some of the options within the HII configuration utility are not present if the controller does not support the corresponding featu...

Page 44: ...plays information about the availability of Battery Backup Unit BBU Enclosure displays information about the number of enclosures connected to the controller Physical Disks displays information about the number of physical disks connected to the controller Disk Groups displays information about the number of disk groups connected to the controller Virtual Disks displays information about the numbe...

Page 45: ...tual disk on unconfigured physical disks Free Capacity utilizes unused physical disk capacity that is already part of a virtual disk Select Physical Disks If you want to select the physical disks from which the virtual disks are being created click Select Physical Disks This option is displayed if you select Unconfigured Capacity as your physical disk capacity Select Disk Groups If you want to sel...

Page 46: ...the read cache policy is set to Read Ahead Write Policy Displays the controller write cache policy You can set the write policy to Write through the controller sends a data transfer completion signal to the host when the disk subsystem has received all the data in a transaction Write back the controller sends a data transfer completion signal to the host when the controller cache has received all ...

Page 47: ...splayed Capacity Allocation displays all the virtual disks associated with the specific disk group It also provides information about the available free space Secured displays whether the disk group is secured or not Deleting Configurations 1 Enter the Dell PERC 10 Configuration Utility See Navigating to Dell PERC 10 configuration utility 2 Click Main Menu Configuration Management Clear Configurat...

Page 48: ...y 4 Click Ok Managing link speed 1 Enter the Dell PERC 10 Configuration Utility See Navigating to Dell PERC 10 configuration utility 2 Click Main Menu Controller Management Advanced Controller Management 3 Click Manage Link Speed You can view change the physical disk settings for the controller if required The possible options are Auto 3 Gbps 6 Gbps 12 Gbps 4 Click Ok to save the changes NOTE To r...

Page 49: ...urther changes Prior to the next reboot All configuration commands are blocked Controller firmware flash is not allowed Following the reboot the mode transition will be complete and the controller will resume normal operation Changing profile using HII Configuration Utility Perform the following steps to change the profile to HII configuration utility 1 Enter the Dell PERC 10 Configuration Utility...

Page 50: ... Utility See Navigating to Dell PERC 10 configuration utility 2 Click Main Menu Controller Management Advanced Controller Properties 3 Click Physical Disk Power Management The following list of options is displayed Time Interval for Spin Down allows the user to specify the delay time before a disk is spun down Spin Down Hot Spare allows you to enable or disable the spin down of hot spare disks Spi...

Page 51: ...Management Advanced Controller Properties 3 In the Controller Properties section set the Auto Import Foreign Configuration option to Enabled 4 Click Apply Changes The auto import is enabled successfully Disabling auto import 1 Enter the Dell PERC 10 Configuration Utility See Navigating to Dell PERC 10 configuration utility 2 Click Main Menu Controller Management Advanced Controller Properties 3 In...

Page 52: ...w 4K devices To view all the virtual disks created navigate to the Virtual Disk Management screen in HII For more information see Virtual disk management NOTE If no boot device is selected the first virtual disk will be set as the boot device on the next reboot A Non RAID disk will not be auto selected as the boot device 4 Click Apply Changes Boot support is enabled for the selected controller Vir...

Page 53: ... sector size of this virtual disk Strip Element Size Indicates the strip element size for the virtual disk Status Indicates the status of the virtual disk Secured Indicates whether the virtual disk is secured or not Bad Blocks Indicates whether the virtual disk has corrupted blocks Viewing physical disks associated with a virtual disk 1 Enter the Dell PERC 10 Configuration Utility See Navigating t...

Page 54: ...nsider the workload intended RAID1 for simple boot disk RAID5 or 6 for file or web servers sequential reads writes of files RAID10 for transactional database small random reads and writes Virtual disks configured on hard drives should use the controller default cache setting of Write Back and Read Ahead Virtual disks configured on SSDs can use the same controller defaults settings as hard drives M...

Page 55: ...To enable expand virtual disk feature from the HII Configuration Utility perform the following steps 1 Enter the Dell PERC 10 Configuration Utility See Navigating to Dell PERC 10 configuration utility 2 Click Main Menu Virtual Disk Management The list of virtual disks is displayed 3 Select the virtual disk 4 From the Operations drop down menu select Expand Virtual Disk NOTE You can view the Expand...

Page 56: ...rm on the selected physical disk The options are Blink Unblink Force Offline Replace Member Erase Options Global and Dedicated hotspare Convert to RAID Capable Convert to Non RAID Disk Device ID Unique identifier of the physical disk Connection Number of paths and how wide the paths are to the physical disk Indicated if a physical disk is in a multipath configuration for H745P MX and H840 Backplan...

Page 57: ...f the physical disk SAS Address SAS address of the physical disk Physical Disk Power State Power condition On or Power Save of the physical disk Disk Cache Settings Disk cache settings NOTE Disk cache for SATA Gen3 drives is disabled by default Hard Disk Drive RPM RPM of the hard drive Available Space Available size of the physical disk Used Space Configured space of the physical disk Disk protoco...

Page 58: ...Dell PERC 10 configuration utility 2 Click Main Menu Physical Disk Management The list of physical disks is displayed 3 Select a physical disk 4 From the Operations drop down menu select Physical Disk Erase NOTE If the drive installed is neither SED or ISE capable then only the Physical Disk Erase option is displayed 5 Click Go A screen is displayed asking if you are sure you want to perform the o...

Page 59: ...ell PERC 10 Configuration Utility See Navigating to Dell PERC 10 configuration utility 2 Click Main Menu Physical Disk Management The list of physical disks appears 3 Select the physical disk 4 From the Operations drop down menu select Convert to RAID capable 5 Click Go A screen appears asking if you are sure you want to perform the operation 6 Select the Confirm option 7 Click Yes The dedicated h...

Page 60: ... Displays whether the voltage status of the battery is normal or high Current Displays power consumption of the battery in milliamps mA Full Capacity Displays the maximum charge capacity of the battery Remaining Capacity Displays the current charge capacity of the battery Expected Margin of Error Displays expected margin of error Completed Discharge Cycles Displays the completed discharge cycles L...

Page 61: ... for PERC cards The Controller Management screen displays controller information and action menus You can perform the following security related actions through the controller management menu Security Key Management Creates changes or deletes the security settings on a controller The Virtual Disk Management screen displays physical disk information and action menus You can perform the following se...

Page 62: ...hrase again 9 Select the I recorded the Security Settings for Future Reference option 10 Click Enable Security The Security Key is created successfully Changing Security Settings 1 Enter the Dell PERC 10 Configuration Utility See Navigating to Dell PERC 10 configuration utility 2 Click Main Menu Controller Management Advanced Controller Management Change Security Settings 3 Select security identif...

Page 63: ...g virtual disk 1 Enter the Dell PERC 10 Configuration Utility See Navigating to Dell PERC 10 configuration utility 2 Click Main Menu Virtual Disk Management The list of virtual disks is displayed 3 Select a virtual disk 4 From the Operations drop down menu select Secure Virtual Disk NOTE The virtual disks can be secured only when the virtual disks are in Optimal state Importing secure virtual disk...

Page 64: ...y errors Preserved Cache State Security key errors General issues Physical disk issues SMART errors Replace member errors Linux operating system errors Disk carrier LED indicators HII error messages Adapter at baseport not responding error message Error Message Adapter at Baseport xxxx is not responding where xxxx is the baseport of the controller Corrective Action Contact Dell Technical Support B...

Page 65: ...ffline so the cached data cannot be written to disk If this is an unexpected error then please power off your system and check your cables to ensure all disks are present If you continue the data in cache will be permanently discarded Press X to acknowledge and permanently destroy the cached data Probable Cause The controller preserves the dirty cache from a virtual disk if the disk becomes offlin...

Page 66: ...m Probable Cause This message is displayed when the HII detects more than four enclosures connected to a single SAS connector Corrective Action You must remove all additional enclosures and restart your system Foreign configuration found error message Error Message Foreign configuration s found on adapter Press any key to continue or C to load the configuration utility or F to import foreign confi...

Page 67: ... console to indicate that the cache was discarded and generates an event If a multi bit error occurs at run time either in code data or in the cache the controller stops The controller logs an event to the controller s internal event log and a message during POST is displayed indicating a multi bit error has occurred NOTE In case of a multi bit error contact Dell Technical Support Preserved Cache ...

Page 68: ...ished security key present on the controller and there cannot be any configured secured disks If there are configured secured virtual disks remove or delete them Failure of Cryptographic Erase task on secured physical disks Cryptographic Erase is the process of securely erasing all data permanently on an encryption capable physical disk and resetting the security attributes It is used in a couple ...

Page 69: ...gured Corrective Action Update the PERC cards to the latest firmware available on Dell com support Replace the drive and ensure not to use the blocked drive Multiple disks become inaccessible Issue Rebuilding the physical disks after multiple disks become simultaneously inaccessible Corrective Action Multiple physical disk errors in a single array typically indicate a failure in cabling or connect...

Page 70: ...ilding the physical disk NOTE You can use the HII Configuration Utility or Dell OpenManage storage management application to perform a manual rebuild of an individual physical disk Virtual disk fails during rebuild using a global hot spare Issue A virtual disk fails during rebuild while using a global hot spare Description The global hot spare reverts to Hotspare state and the virtual disk is in F...

Page 71: ...ack up your data 2 Force the physical disk offline NOTE If a hot spare is present the rebuild starts with the hot spare after the disk is forced offline 3 Replace the disk with a new physical disk of equal or higher capacity 4 Perform the Replace Member operation NOTE The Replace Member operation allows you to copy data from a source physical disk of a virtual disk to a target physical disk that i...

Page 72: ... is assumed as write through error message Error Date Time HostName kernel sdb asking for cache data failed Date Time HostName kernel sdb assuming drive cache write through Corrective Action The error message is displayed when the Linux Small Computer System Interface SCSI mid layer asks for physical disk cache settings The controller firmware manages the virtual disk cache settings on a per contr...

Page 73: ...node This action is not supported Disk carrier LED indicators Each hard drive carrier has an activity indicator and a status indicator The indicators provide information about the current status of the hard drive The activity LED indicates whether hard drive is currently in use or not The status LED indicates the power condition of the hard drive Figure 12 Hard drive indicators 1 activity LED 2 st...

Page 74: ... in Boot Manager for details Probable Cause This message might indicate that the cables are not connected the disks might be missing or the UEFI driver might require configuration changes Corrective Action 1 Check if the cables are connected properly or replace missing hard drives if any and then restart the system 2 Press any key to load the driver health manager to display the configurations The...

Page 75: ...physical disk RAID 1 is good for small databases or other applications that require small capacity and complete data redundancy RAID 5 uses disk striping and parity data across all physical disks distributed parity to provide high data throughput and data redundancy especially for small random access RAID 6 is an extension of RAID 5 and uses an additional parity block RAID 6 uses block level strip...

Page 76: ... to disk 2 and so on Disk striping enhances performance because multiple physical disks are accessed simultaneously but disk striping does not provide data redundancy Figure 13 Example of disk striping RAID 0 Disk mirroring With mirroring used in RAID 1 data written to one disk is simultaneously written to another disk If one disk fails the contents of the other disk can be used to run the system ...

Page 77: ...te user data Parity data is present for RAID 5 6 50 and 60 The parity data is distributed across all the physical disks in the system If a single physical disk fails it can be rebuilt from the parity and the data on the remaining physical disks RAID level 5 combines distributed parity with disk striping Parity provides redundancy for one physical disk failure without duplicating the contents of th...

Page 78: ... the drop down menu on the lower right corner of the page 3 For customized support a Enter your system Service Tag in the Enter your Service Tag field b Click Submit The support page that lists the various support categories is displayed 4 For general support a Select your product category b Select your product segment c Select your product The support page that lists the various support categorie...

Reviews: