Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

Chapter

Administering

cluster functionality

A cluster consists of a number of hosts or nodes that share a set of disks. The main benefits

of cluster configurations are:

The cluster functionality of Veritas Volume Manager (CVM) allows up to 16 nodes in a

cluster to simultaneously access and manage a set of disks under VxVM control (VM

disks). The same logical view of disk configuration and any changes to this is available on

all the nodes. When the cluster functionality is enabled, all the nodes in the cluster can

share VxVM objects. This chapter discusses the cluster functionality that is provided with

VxVM.

Note: You need an additional license to use this feature.

Availability If one node fails, the other nodes can still access the shared disks. When

configured with Serviceguard, HP’s cluster management software,

mission-critical applications can continue running by transferring their

execution to a standby node in the cluster. This ability to provide

continuous uninterrupted service by switching to redundant hardware is

commonly termed failover.

Failover is transparent to users and high-level applications for database

and file-sharing. You must configure to monitor systems and services,

and to restart applications on another node in the event of either

hardware or software failure. VCS also allows you to perform general

administration tasks such as making nodes join or leave a cluster.

Off-host processing Clusters can reduce contention for system resources by performing

activities such as backup, decision support and report generation on the

more lightly loaded nodes of the cluster. This allows businesses to

derive enhanced value from their investment in cluster systems.