vsphere-esxi-vcenter-server-55-storage-guide

Chapter 24 Storage Hardware AccelerationOn your host, the hardware acceleration is enabled by default. If your storage does not support thehardware acceleration, you can disable it.In addition to hardware acceleration support, ESXi includes support for array thin provisioning. Forinformation, see “Array Thin Provisioning and VMFS Datastores,” on page 249.Disable Hardware Acceleration for Block Storage Devices in thevSphere Web ClientOn your host, the hardware acceleration for block storage devices is enabled by default. You can use thevSphere Web Client advanced settings to disable the hardware acceleration operations.As with any advanced settings, before you disable the hardware acceleration, consult with the VMwaresupport team.Procedure1 Browse to the host in the vSphere Web Client navigator.2 Click the Manage tab, and click Settings.3 Under System, click Advanced System Settings.4 Change the value for any of the options to 0 (disabled):• VMFS3.HardwareAcceleratedLocking• DataMover.HardwareAcceleratedMove• DataMover.HardwareAcceleratedInitManaging Hardware Acceleration on Block Storage DevicesTo integrate with the block storage arrays and to benefit from the array hardware operations, vSphere usesthe ESXi extensions referred to as Storage APIs - Array Integration, formerly called VAAI.In the vSphere 5.x release, these extensions are implemented as the T10 SCSI based commands. As a result,with the devices that support the T10 SCSI standard, your ESXi host can communicate directly and does notrequire the VAAI plug-ins.If the device does not support T10 SCSI or provides partial support, ESXi reverts to using the VAAI plugins,installed on your host, or uses a combination of the T10 SCSI commands and plug-ins. The VAAI pluginsare vendor-specific and can be either VMware or partner developed. To manage the VAAI capabledevice, your host attaches the VAAI filter and vendor-specific VAAI plug-in to the device.For information about whether your storage requires VAAI plug-ins or supports hardware accelerationthrough T10 SCSI commands, see the vSphere Compatibility Guide or check with your storage vendor.You can use several esxcli commands to query storage devices for the hardware acceleration supportinformation. For the devices that require the VAAI plug-ins, the claim rule commands are also available. Forinformation about esxcli commands, see Getting Started with vSphere Command-Line Interfaces.Display Hardware Acceleration Plug-Ins and FilterTo communicate with the devices that do not support the T10 SCSI standard, your host uses a combinationof a single VAAI filter and a vendor-specific VAAI plug-in. Use the esxcli command to view the hardwareacceleration filter and plug-ins currently loaded into your system.In the procedure, --server=server_name specifies the target server. The specified target server prompts youfor a user name and password. Other connection options, such as a configuration file or session file, aresupported. For a list of connection options, see Getting Started with vSphere Command-Line Interfaces.VMware, Inc. 237