Using Cluster File Systems

In the SunPlex system, all multihost disks are placed into disk device groups, which can be Solaris Volume Manager disksets, VxVM disk groups, or individual disks not under control of a software-based volume manager.

For a cluster file system to be highly available, the underlying disk storage must be connected to more than one node. Therefore, a local file system (a file system that is stored on a node's local disk) that is made into a cluster file system is not highly available.

As with normal file systems, you can mount cluster file systems in two ways:

• Manually: Use the mount command and the -g or -o global mount options to mount the cluster file system from the command line, for example:

  # mount -g /dev/global/dsk/d0s0 /global/oracle/data

• Automatically: Create an entry in the /etc/vfstab file with a global mount option to mount the cluster file system at boot. You then create a mount point under the /global directory on all nodes. The directory /global is a recommended location, not a requirement. Here's a sample line for a cluster file system from an /etc/vfstab file:

  /dev/md/oracle/dsk/d1 /dev/md/oracle/rdsk/d1 /global/oracle/data ufs 2 yes global,logging

While Sun Cluster software does not impose a naming policy for cluster file systems, you can ease administration by creating a mount point for all cluster file systems under the same directory, such as /global/disk-device-group. See Sun Cluster 3.1 Software Installation Guide and Sun Cluster 3.1 System Administration Guide for more information.