After you install your PVFS2 I/O Nodes and optionally a PVFS2 Metadata Server, you need to reinstall all your client nodes (e.g., your compute nodes). This will install the PVFS2 client software on the nodes so each node can mount the PVFS2 file system.
To reinstall your compute nodes, as root execute:
# tentakel -g compute /boot/kickstart/cluster-kickstart |