I/O filters can gain direct access to the virtual machine I/O path. You can enable the I/O filter for an individual virtual disk level. The I/O filters are independent of the storage topology.

VMware offers certain categories of I/O filters. In addition, third-party vendors can create the I/O filters. Typically, they are distributed as packages that provide an installer to deploy the filter components on vCenter Server and ESXi host clusters.

After the I/O filters are deployed, vCenter Server configures and registers an I/O filter storage provider, also called a VASA provider, for each host in the cluster. The storage providers communicate with vCenter Server and make data services offered by the I/O filter visible in the VM Storage Policies interface. You can reference these data services when defining common rules for a VM policy. After you associate virtual disks with this policy, the I/O filters are enabled on the virtual disks.

Datastore Support

I/O filters can support all datastore types including the following:
  • VMFS
  • NFS 3
  • NFS 4.1
  • Virtual Volumes (VVol)
  • vSAN