6.0.1

Hardware Acceleration Requirements
The hardware acceleration functionality works only if you use an appropriate host and storage array
combination.
Table 23‑1. Hardware Acceleration Storage Requirements
ESXi Block Storage Devices NAS Devices
ESXi version 6.0 Support T10 SCSI standard, or block
storage plug-ins for array integration
(VAAI)
Support NAS plug-ins for array
integration
N NFS 4.1 does not support
hardware acceleration.
N If your SAN or NAS storage fabric uses an intermediate appliance in front of a storage system that
supports hardware acceleration, the intermediate appliance must also support hardware acceleration and be
properly certied. The intermediate appliance might be a storage virtualization appliance, I/O acceleration
appliance, encryption appliance, and so on.
Hardware Acceleration Support Status
For each storage device and datastore, the vSphere Web Client display the hardware acceleration support
status.
The status values are Unknown, Supported, and Not Supported. The initial value is Unknown.
For block devices, the status changes to Supported after the host successfully performs the ooad operation.
If the ooad operation fails, the status changes to Not Supported. The status remains Unknown if the
device provides partial hardware acceleration support.
With NAS, the status becomes Supported when the storage can perform at least one hardware ooad
operation.
When storage devices do not support or provide partial support for the host operations, your host reverts to
its native methods to perform unsupported operations.
Hardware Acceleration for Block Storage Devices
With hardware acceleration, your host can integrate with block storage devices, Fibre Channel or iSCSI, and
use certain storage array operations.
ESXi hardware acceleration supports the following array operations:
n
Full copy, also called clone blocks or copy ooad. Enables the storage arrays to make full copies of data
within the array without having the host read and write the data. This operation reduces the time and
network load when cloning virtual machines, provisioning from a template, or migrating with vMotion.
n
Block zeroing, also called write same. Enables storage arrays to zero out a large number of blocks to
provide newly allocated storage, free of previously wrien data. This operation reduces the time and
network load when creating virtual machines and formaing virtual disks.
n
Hardware assisted locking, also called atomic test and set (ATS). Supports discrete virtual machine
locking without use of SCSI reservations. This operation allows disk locking per sector, instead of the
entire LUN as with SCSI reservations.
Check with your vendor for the hardware acceleration support. Certain storage arrays require that you
activate the support on the storage side.
On your host, the hardware acceleration is enabled by default. If your storage does not support the
hardware acceleration, you can disable it.
vSphere Storage
260 VMware, Inc.