Clustering and RDM
VirtuCache cannot be used with any clustered products that require sharing a virtual disk between VMs. This applies to Active-Passive HA cluster products like Microsoft Clustering Services (MSCS), VERITAS Clustering Services (VCS) and Active-Active cluster products like Oracle Real Application Cluster (RAC) in use by Guest VMs. The more commonly used VMware native cluster and HA configuration is fully supported. As Microsoft Exchange Database Availability (DAG) is not a technology that shares virtual disks between VMs, it is supported as well.
Disks are typically RDMed to VMs so that filesystems other than VMFS and clustering software other than VMware’s can be deployed within VMs. A good example is Microsoft Clustering. Since VirtuCache supports only VMware clustering and VMFS filesystems, disks that have been RDMed for the specific purpose of supporting third party Clustering Software and File Systems need to specifically excluded from caching