VERITAS File System 4.1 Administrator's Guide

The VERITAS File System
Cluster File Systems
Chapter 1 31
Cluster File Systems
Clustered file systems are an extension of VxFS that support concurrent direct media access
from multiple systems. CFS employs a master/slave protocol. All cluster file systems can read
file data directly from a shared disk. In addition, all systems can write "in-place" file data.
Operations that require changes to file system metadata, such as allocation, creation, and
deletion, can only be performed by the single primary file system node. To maintain file
system consistency, secondary nodes must send messages to the primary, and the primary will
perform the operations.
Installing VxFS and enabling the cluster feature does not create a cluster file system
configuration. File system clustering requires other VERITAS products to enable
communication services and provide storage resources. These products are packaged with
VxFS in the Storage Foundation Cluster File System to provide a complete clustering
environment.
See The VERITAS SANPoint Foundation Suite Installation and Configuration Guide,
included in the VERITAS SANPoint Foundation Suite product, for more information.
To be a cluster mount, a file system must be mounted using the mount -o cluster option.
File systems mounted without the -o cluster option are termed local mounts.
CFS functionality is a separately licensable feature.