VCS introduces the VMwareDisks agent to support storage configurations in a VMware virtual environment. The agent is platform independent and supports VMware Virtual Machine Disk (VMDK), Raw Device Mapping (RDM) disk files (virtual), and storage that is configured using Network File System (NFS). The VMwareDisks agent works without SCSI reservations and supports locally attached non-shared storage.

VMware features such as snapshots, vMotion, and DRS do not work when SCSI disks are shared between virtual machines. The VMwareDisks agent is designed to address this limitation. With this agent, the disks can now be attached to a single virtual machine at a time in the VCS cluster. On failover, along with the service group, the VMwareDisks agent moves the disks to the target virtual machine.

The VMwareDisks agent communicates with the host ESXi server to configure storage. This agent manages the disk attach and detach operations on a virtual machine in the VCS cluster. The agent is VMware HA aware. During failovers, the agent detaches the disk from one system and then attaches it to the system where the application is actively running. The VMwareDisks agent presents the virtual disks to the operating system. On Windows, the agent relies on the VMNSDg agent (in case of SFW-managed local storage) and the NativeDisks agent (in case of LDM-managed local storage) for initializing and managing the virtual disks. On Linux, the agent relies on the LVM and VxVM agents.