Dell UCPM-800 manual FastPath, Virtual Disk Migration, Using Physical Disk Roaming

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Using Physical Disk Roaming

Perform the following steps to use disk roaming:

1.Turn off the power to the system, physical disks, enclosures, and system components.

2.Disconnect power cables from the system.

3.Move the physical disks to the required positions on the backplane or the enclosure.

4.Perform a safety check. Make sure the physical disks are inserted properly.

5.Turn on the system.

The controller detects the RAID configuration from the configuration data on the physical disks.

FastPath

The Shared PERC 8 card supports FastPath feature, which improves application performance by delivering high I/O per second (IOPS).

Under specific conditions with FastPath, the I/O bypasses the controller cache and is committed directly to the physical disk from the host memory or directly from the physical disk. All simple non-spanned virtual disks configured with Write-Through write-cache policy and No Read-Ahead read-cache policy can utilize FastPath.

Workloads on SSD volumes provide the most performance improvement with FastPath.

The following conditions support FastPath:

•Random workloads with small blocks.

•I/O block sizes smaller than virtual disk’s stripe size.

•Sequential read workloads on unspanned RAID volumes (RAID 0, RAID 1, RAID 5, and RAID 6).

•Sequential read and write workloads on RAID 0 virtual disks.

The following conditions do not support FastPath

•Virtual disks running background operations like rebuild, initialization, and so on.

•Spanned RAID volumes like RAID 10, RAID 50, and RAID 60.

Virtual Disk Migration

The Shared PERC 8 card supports migration of virtual disks from one controller to another without taking the target controller offline. The controller can import RAID virtual disks in optimal, degraded, or partially degraded states.

Conditions that do not support virtual virtual disk migration:

•Does not support migration of virtual disk that is in a failed state.

•Does not support migration of virtual disk when the source system is turned on.

Conditions that support virtual virtual disk migration:

•Supports migration of virtual disks from a similar Shared PERC 8 card.

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Contents User’s Guide Page Contents Driver Installation Deploying The Shared Perc 8 CardGetting help Configurations of the Shared Perc 8 card About The Shared Perc 8 CardSpecifications of a Shared Perc 8 card Storage Subsystem Compatibility Matrix at dell.comPage Related Documentation Supported Operating SystemsBest Practices For Shared Perc Locating your system Service Tag Contacting DellDocumentation Feedback Consistency Checks Shared Perc 8 Card FeaturesPhysical Disk Power Management Virtual Disk InitializationFull Initialization Of Virtual Disks Physical Disk RoamingBackground Initialization Of Virtual Disks Fast Initialization Of Virtual DisksVirtual Disk Migration Using Physical Disk RoamingFastPath Migrating Virtual Disks If The Target System Is Turned On Virtual Disk Cache PoliciesMigrating Virtual Disks If The Target System Is Turned Off Conditions Under Which Write-Back Is Employed Virtual Disk Write Cache PoliciesWrite-Back Write-throughConditions under which write-through is employed Fault TolerancePhysical Disk Write Cache Policy Virtual Disk Read Cache PoliciesSmart Feature Patrol ReadShared Perc 8 Card Cache Preservation Physical disk failure detectionPhysical Disk Hot Swapping Battery Transparent Learn Cycle Controller Failover FeatureMultipath Support Configuring Multipath Support In WindowsConfiguring Multipath Support In VMWare Multipath support in LinuxReplacing a Shared Perc 8 Card Installing a New Shared Perc 8 CardDeploying The Shared Perc 8 Card Prerequisites For Removing The Shared Perc 8 Card Removing The Shared Perc 8 CardRemoving and Installing the Shared Perc 8 Card Installing The Shared Perc 8 Card Post-Installation Tasks For Shared Perc 8 CardFirmware installation or update Updating firmwareDriver Installation Installing Or Updating Windows Drivers For Shared Perc Installing Or Updating Linux Drivers For Shared Perc Installing Or Updating VMware Drivers For Shared PercManagement Applications For Shared Perc 8 Card Troubleshooting Shared Perc 8 Card Boots Into Safe ModeShared Perc 8 Card Not Seen In Device Manager General IssuesDegraded State Of Virtual Disks Shared Perc 8 Cards Fail To Function Physical disk issuesUnable to rebuild a fault tolerant virtual disk Physical Disk In Failed StateRebuilding a Failed Physical Disk Fatal Error Or Data Corruption ReportedMultiple Disks Become Inaccessible Physical disk takes a long time to rebuild Virtual Disk Fails During Rebuild Using a Global Hot SpareController cache issues Smart Errors Target Disk Fails Auto Replacement Member ErrorsSource Disk Fails General Disk FailsHard-Drive Indicator Patterns Hard-Drive IndicatorsGetting help Documentation feedback