A shared storage device is required. The storage must be configured to allocate a separate block device to each PVFS daemon, and all nodes (including spares) must be capable of accessing all block devices.
One way of achieving this is by using a SAN. In the examples used in this document, the SAN has been divided into 4 LUNs. Each of the 5 nodes in the cluster is capable of mounting all 4 LUNs. The Heartbeat software will insure that a given LUN is mounted in only one location at a time.
Each block device should be formatted with a local file system. This document assumes the use of ext3. Unique labels should be set on each file system (for example, using the -L argument to mke2fs or tune2fs). This will allow the block devices to be mounted by consistent labels regardless of how Linux assigned device file names to the devices.