The cluster service uses the Physical Disk resource type to manage disks that are on a cluster storage device. Disks must have the same drive letters on all cluster nodes.

To prevent data corruption, only one node at a time can use a cluster disk. Cluster Service normally prevents more than one node from using a disk at the same time. However, there are some circumstances not protected by ordinary cluster safeguards: when you install a new disk, and when you remove a disk from a cluster. For more information, see the Windows Server documentation.

The Ingres system, data, and related files must exist on a Physical Disk resource type.