Common rules are based on data services that are generic for all types of storage and do not depend on a datastore. These additional services become available in the VM Storage Policies interface when you install third-party I/O filters developed through vSphere APIs for I/O Filtering. You can reference these data services in a VM storage policy.

Unlike storage-specific rules, common rules do not define storage placement and storage requirements for a virtual machine, but ensure that additional data services, such as I/O filters, become enabled for the virtual machine. No matter which datastore the virtual machine runs on, the enabled filters can provide the following services:
  • Caching. Configures a cache for virtual disk data. The filter can use a local cache or a flash storage device to cache the data and increase the Input/Output Operations Per Second and hardware utilization rates for the virtual disk.
  • Replication. Replicates virtual machine or virtual disks to external targets such as another host or cluster.

For more information about I/O filters, see Filtering Virtual Machine I/O.