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

The /etc/fstab file
In the /etc/fstab file, do not specify any cluster file systems to mount-at-boot
because mounts initiated from fstab occur before cluster configuration begins.
For cluster mounts, use the VCS configuration file to determine which file systems
to enable following a reboot.
When the Storage Foundation Cluster File System primary fails
If the server on which the SFCFS primary is running fails, the remaining cluster
nodes elect a new primary. The new primary reads the file system intent log and
completes any metadata updates that were in process at the time of the failure.
Application I/O from other nodes may block during this process and cause a delay.
When the file system is again consistent, application processing resumes.
Because nodes using a cluster file system in secondary node do not update file
system metadata directly, failure of a secondary node does not require metadata
repair. SFCFS recovery from secondary node failure is therefore faster than from
primary node failure.
Distribute the load on a cluster
Distributing the workload in a cluster provides performance and failover
advantages.
For example, if you have eight file systems and four nodes, designating two file
systems per node as the primary would be beneficial. Primaryship is determined
by which node first mounts the file system. You can also use the fsclustadm to
designate a SFCFS primary. The fsclustadm setprimary command can also
define the order in which primaryship is assumed if the current primary fails.
After setup, the policy is in effect as long as one or more nodes in the cluster have
the file system mounted.
Storage Checkpoints on Storage Foundation Cluster File System
See the Veritas Storage Foundation Advanced Features Administrator's Guide for
how to create and maintain Storage Checkpoints. The creation of Storage
Checkpoints works the same on CFS file systems as they do on local mount file
systems.
Snapshots on Storage Foundation Cluster File System
A snapshot provides a consistent point-in-time image of a VxFS file system. A
snapshot can be accessed as a read-only mounted file system to perform efficient
61Administering Storage Foundation Cluster File System and its components
Administering CFS