Technical data

• Optionally, one disk on a shared SCSI bus to act as the quorum disk (see
Section 1.3.1.4). For a more detailed discussion of the quorum disk, see
the
Cluster Administration manual.
The following sections provide more information about these disks.
Figure 1–1 shows a generic two-member cluster with the required file
systems.
1.3.1.1 Tru64 UNIX Operating System Disk
The Tru64 UNIX operating system is installed using AdvFS file systems on
one or more disks that are accessible to the system that will become the
first cluster member. For example:
dsk0a root_domain#root
dsk0g usr_domain#usr
dsk0h var_domain#var
The operating system disk (Tru64 UNIX disk) cannot be used as a
clusterwide disk, as a member boot disk, or as the quorum disk.
Because the Tru64 UNIX operating system will be available on the first
cluster member, in an emergency, after shutting down the cluster, you have
the option of booting the Tru64 UNIX operating system and attempting to fix
the problem. See the Cluster Administration manual for more information.
1.3.1.2 Clusterwide Disks
When you create a cluster, the installation scripts copy the Tru64 UNIX
root (/), /usr, and /var file systems from the Tru64 UNIX disk to the disk
or disks you specify.
We recommend that the disk or disks that you use for the clusterwide file
systems be placed on a shared SCSI bus so that all cluster members have
access to these disks.
During the installation, you supply the disk device names and partitions
that will contain the clusterwide root (/), /usr, and /var file systems. For
example, dsk3b, dsk4c, and dsk3g:
dsk3b cluster_root#root
dsk4c cluster_usr#usr
dsk3g cluster_var#var
The /var fileset cannot share the cluster_usr domain, but must be a
separate domain, cluster_var. Each AdvFS file system must be a separate
partition; the partitions do not have to be on the same disk.
If any partition on a disk is used by a clusterwide file system, only
clusterwide file systems can be on that disk. A disk containing a clusterwide
Introduction 1–3