Dell UCPM-800 manual Configuring Multipath Support In Windows, Multipath support in Linux

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Multipath Support

Multipathing solutions use redundant physical path components such as adapters, cables, and switches to create logical paths between the server and the storage device. In the event that one or more of these components fails, multipathing logic uses an alternate path for I/O so that applications can still access their data.

In the Fault Tolerant Shared PERC 8 card configuration, the PowerEdge VRTX system has two Shared PERC 8 cards in an active-passive mode. In this configuration, each host server can access the same virtual disk through both cards. In the absence of a multipath driver, the operating system identifies the single disk as two identical disks. The multipath driver aggregates the two disks into a single disk with redundant access that is then presented to the operating system. The MPIO driver determines the path chosen for any I/O sent to the virtual disk. Any I/O directed to the passive card is internally redirected to the active card for completion.

Configuring Multipath Support In Windows

In Windows, multipath support is enabled by installing the MPIO driver. The Shared PERC 8 device must be added to the list of devices that are aggregated by MPIO after the device driver is installed. Perform the following steps to add the Shared PERC 8 card:

1.Open the MPIO control panel.

2.Click the Discover Multi-Paths tab.

3.Select DELL Shared PERC8 and click Add.

This is only a one time setup procedure. After the Shared PERC 8 device is added to the list of devices, the MPIO driver aggregates all instances of the same virtual disk into a single one. The recommended multipath policy for Windows is round-robin (with subset).

Configuring Multipath Support In VMWare

In VMWare, multipath support is automatically enabled using Native Multipathing (NMP) for all Shared PERC 8 cards in Dell versions of the ESXi operating systems.

NOTE: The recommended multipath policy is Most Recently Used (MRU).

Multipath support in Linux

Currently, Linux support is not offered by Dell on fault tolerant VRTX configurations.

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Contents User’s Guide Page Contents Deploying The Shared Perc 8 Card Driver InstallationGetting help About The Shared Perc 8 Card Configurations of the Shared Perc 8 cardStorage Subsystem Compatibility Matrix at dell.com Specifications of a Shared Perc 8 cardPage Supported Operating Systems Best Practices For Shared PercRelated Documentation Contacting Dell Locating your system Service TagDocumentation Feedback Physical Disk Power Management Shared Perc 8 Card FeaturesConsistency Checks Virtual Disk InitializationBackground Initialization Of Virtual Disks Physical Disk RoamingFull Initialization Of Virtual Disks Fast Initialization Of Virtual DisksUsing Physical Disk Roaming FastPathVirtual Disk Migration Virtual Disk Cache Policies Migrating Virtual Disks If The Target System Is Turned OffMigrating Virtual Disks If The Target System Is Turned On Write-Back Virtual Disk Write Cache PoliciesConditions Under Which Write-Back Is Employed Write-throughPhysical Disk Write Cache Policy Fault ToleranceConditions under which write-through is employed Virtual Disk Read Cache PoliciesPatrol Read Smart FeaturePhysical disk failure detection Physical Disk Hot SwappingShared Perc 8 Card Cache Preservation Controller Failover Feature Battery Transparent Learn CycleConfiguring Multipath Support In VMWare Configuring Multipath Support In WindowsMultipath Support Multipath support in LinuxInstalling a New Shared Perc 8 Card Deploying The Shared Perc 8 CardReplacing a Shared Perc 8 Card Removing The Shared Perc 8 Card Prerequisites For Removing The Shared Perc 8 CardRemoving and Installing the Shared Perc 8 Card Post-Installation Tasks For Shared Perc 8 Card Installing The Shared Perc 8 CardUpdating firmware Firmware installation or updateDriver Installation Installing Or Updating Windows Drivers For Shared Perc Installing Or Updating VMware Drivers For Shared Perc Installing Or Updating Linux Drivers For Shared PercManagement Applications For Shared Perc 8 Card Shared Perc 8 Card Boots Into Safe Mode TroubleshootingGeneral Issues Degraded State Of Virtual DisksShared Perc 8 Card Not Seen In Device Manager Unable to rebuild a fault tolerant virtual disk Physical disk issuesShared Perc 8 Cards Fail To Function Physical Disk In Failed StateFatal Error Or Data Corruption Reported Multiple Disks Become InaccessibleRebuilding a Failed Physical Disk Virtual Disk Fails During Rebuild Using a Global Hot Spare Controller cache issuesPhysical disk takes a long time to rebuild Smart Errors Source Disk Fails Auto Replacement Member ErrorsTarget Disk Fails General Disk FailsHard-Drive Indicators Hard-Drive Indicator PatternsDocumentation feedback Getting help