6.5.1

Table Of Contents
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NFS 3
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NFS 4.1
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Virtual Volumes (VVol)
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vSAN
Types of I/O Filters
VMware provides certain categories of I/O filters that are installed on your ESXi hosts. In addition,
VMware partners can create the I/O filters through the vSphere APIs for I/O Filtering (VAIO) developer
program. The I/O filters can serve multiple purposes.
The supported types of filters include the following:
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Replication. Replicates all write I/O operations to an external target location, such as another host or
cluster.
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Encryption. Offered by VMware. Provides encryption mechanisms for virtual machines. For more
information, see the vSphere Security documentation.
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Caching. Implements a cache for virtual disk data. The filter can use a local flash storage device to
cache the data and increase the IOPS and hardware utilization rates for the virtual disk. If you use the
caching filter, you might need to configure a Virtual Flash Resource.
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Storage I/O control. Offered by VMware. Throttles the I/O load towards a datastore and controls the
amount of storage I/O that is allocated to virtual machines during periods of I/O congestion. For more
information, see the vSphere Resource Management documentation.
Note You can install several filters from the same category, such as caching, on your ESXi host.
However, you can have only one filter from the same category per virtual disk.
I/O Filtering Components
Several components are involved in the I/O filtering process.
The components of I/O filtering include the following:
VAIO Filter Framework A combination of user world and VMkernel infrastructure provided by ESXi.
With the framework, you can add filter plug-ins to the I/O path to and from
virtual disks. The infrastructure includes an I/O filter storage provider (VASA
provider). The provider integrates with the Storage Policy Based
Management (SPBM) system and exports filter capabilities to
vCenter Server.
I/O Filter Plug-In A software component provided by VMware or developed by VMware
partners that intercepts and filters I/O data in transit between virtual disks
and guest operating systems.
vSphere Storage
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