About I/O Fencing; About Vcs Optional Components - Symantec Veritas Cluster Server Installation Manual

18 Introducing Veritas Cluster Server

About VCS optional components

About I/O fencing

About VCS optional components
I/O fencing protects the data on shared disks when nodes in a cluster detect a
change in the cluster membership that indicates a split brain condition.
See the Veritas Cluster Server User's Guide.
The fencing operation determines the following:
The nodes that must retain access to the shared storage
The nodes that must be ejected from the cluster
This decision prevents possible data corruption. The installvcs program installs
the VCS I/O fencing driver, VRTSvxfen. To protect data on shared disks, you must
configure I/O fencing after you install and configure VCS.
I/O fencing technology uses coordination points for arbitration in the event of a
network partition.
Note: Symantec recommends that you use I/O fencing to protect your cluster
against split-brain situations.
You can add the following optional components to VCS:
Symantec Product
Authentication Service
Veritas Cluster Server
Management Console
Cluster Manager (Java console)
VCS Simulator
To configure the optional components, make sure to install all RPMs when the
installation program prompts you.
Figure 1-4 illustrates a sample VCS deployment with the optional components
configured.
See "About Symantec Product Authentication Service
(AT)" on page 19.
See "About Veritas Cluster Server Management Console"
on page 20.
See "About Cluster Manager (Java Console)"
See "About VCS Simulator"
on page 20.
on page 20.