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

Different access level privileges permit the user to issue different commands. If
a user is neither a CP server admin nor a CP server operator user, then the user
has guest status and can issue limited commands.
The user types and their access level privileges are assigned to individual users
during SFCFS cluster configuration for fencing. During the installation process,
you are prompted for a user name, password, and access level privilege (CP server
admin or CP server operator).
To administer and operate a CP server, there must be at least one CP server admin.
A root user on a CP server is given all the administrator privileges, and these
administrator privileges can be used to perform all the CP server specific
operations.
About Veritas Volume Manager cluster functionality
Veritas Volume Manager cluster functionality (CVM) allows up to 64 nodes in a
cluster to simultaneously access and manage a set of disks under VxVM control
(VM disks). The same logical view of the disk configuration and any changes are
available on each node. When the cluster functionality is enabled, all cluster nodes
can share VxVM objects. Features provided by the base volume manager, such as
mirroring, fast mirror resync and dirty region logging are also supported in the
cluster environment.
To implement cluster functionality, VxVM works together with the cluster monitor
daemon provided by the host operating system or by VCS. The cluster monitor
informs VxVM of changes in cluster membership. Each node starts up
independently and has its own cluster monitor, plus its own copies of the operating
system and CVM. When a node joins a cluster it gains access to shared disks. When
a node leaves a cluster, it no longer has access to shared disks. A node joins a
cluster when the cluster monitor is started on that node.
Note: RAID-5 volumes are not supported on a shared disk group.
Figure 2-3 illustrates a simple cluster arrangement consisting of four nodes with
similar or identical hardware characteristics (CPUs, RAM and host adapters), and
configured with identical software (including the operating system).
The nodes are fully connected by a private network and they are also separately
connected to shared external storage (either disk arrays or JBODs: just a bunch
of disks) via Fibre Channel. Each node has two independent paths to these disks,
which are configured in one or more cluster-shareable disk groups.
Storage Foundation Cluster File System architecture
About Veritas Volume Manager cluster functionality
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