VERITAS Storage Foundation 4.1 Cluster File System HP Serviceguard Storage Management Suite Extracts, December 2005

VxFS Functionality on Cluster File Systems
6 Installation and Administration Guide
Cluster File System Benefits and Applications
Advantages to Using CFS
CFS simplifies or eliminates system administration tasks that result from hardware
limitations:
◆ The CFS single file system image administrative model simplifies administration by
making all file system management operations, except resizing and reorganization
(defragmentation), independent of the location from which they are invoked.
◆ You can create and manage terabyte-sized volumes, so partitioning file systems to fit
within disk limitations is usually not necessary.
◆ CFS can support file systems with up to 256 terabyte in size, so only extremely large
data farms must be partitioned because of file system addressing limitations.
◆ Because all servers in a cluster have access to CFS cluster-shareable file systems,
keeping data consistent across multiple servers is automatic. All cluster nodes have
access to the same data, and all data is accessible by all servers using single server file
system semantics.
◆ Because all files can be accessed by all servers, applications can be allocated to servers
to balance load or meet other operational requirements. Similarly, failover becomes
more flexible because it is not constrained by data accessibility.
◆ Because each CFS file system can be the primary on any cluster node, the file system
recovery portion of failover time in an
n-node cluster can be reduced by a factor of n
by distributing the primaryship of file systems uniformly across cluster nodes.
◆ Enterprise RAID subsystems can be used more effectively because all of their capacity
can be mounted by all servers, and allocated by using administrative operations
instead of hardware reconfigurations.
◆ Larger volumes with wider striping improve application I/O load balancing. Not
only is the I/O load of each server spread across storage resources, but with CFS
shared file systems, the loads of all servers are balanced against each other.
◆ Extending clusters by adding servers is easier because each new server’s storage
configuration does not need to be set up—new servers simply adopt the cluster-wide
volume and file system configuration.
◆ The clusterized Oracle Disk Manager (ODM) feature that makes file-based databases
perform as well as raw partition-based databases is available to applications running
in a cluster.