Veritas Storage Foundation 5.1 SP1 Cluster File System Administrator"s Guide (5900-1738, April 2011)

failover becomes more flexible because it is not constrained by data
accessibility.
■ Because each SFCFS file system can be on any node in the cluster, the file
system recovery portion of failover time in an n-node cluster can be reduced
by a factor of n by distributing the 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 SFCFS 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.
When to use Storage Foundation Cluster File System
You should use SFCFS for any application that requires the sharing of files, such
as for home directories and boot server files, Web pages, and for cluster-ready
applications. SFCFS is also applicable when you want highly available standby
data, in predominantly read-only environments where you just need to access
data, or when you do not want to rely on NFS for file sharing.
Almost all applications can benefit from SFCFS. Applications that are not
“cluster-aware” can operate on and access data from anywhere in a cluster. If
multiple cluster applications running on different servers are accessing data in
a cluster file system, overall system I/O performance improves due to the load
balancing effect of having one cluster file system on a separate underlying volume.
This is automatic; no tuning or other administrative action is required.
Many applications consist of multiple concurrent threads of execution that could
run on different servers if they had a way to coordinate their data accesses. SFCFS
provides this coordination. Such applications can be made cluster-aware allowing
their instances to co-operate to balance client and data access load, and thereby
scale beyond the capacity of any single server. In such applications, SFCFS provides
shared data access, enabling application-level load balancing across cluster nodes.
SFCFS provides the following features:
Technical overview of Storage Foundation Cluster File System
Storage Foundation Cluster File System benefits and applications
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