Cluster Server Installation Guide for Solaris x64 5.0 - Storage ...

Chapter 1Introducing VCSThis chapter contains the following topics:■■About VCSVCS basicsAbout VCSVCS basicsVeritas Cluster Server by Symantec is a high-availability solution for clusterconfigurations. Veritas Cluster Server (VCS) monitors systems and applicationservices, and restarts services when hardware or software fails.A single VCS cluster consists of multiple systems connected in variouscombinations to shared storage devices. When a system is part of a VCS cluster,it is a node. VCS monitors and controls applications running in the cluster onnodes, and restarts applications in response to a variety of hardware or softwarefaults.Client application continue operation with little or no downtime. In some cases,such as NFS, this continuation is transparent to high-level applications andusers. In other cases, a user might have to retry an operation, such as a webserver reloading a page.Figure 1-1 illustrates a typical VCS configuration of four nodes connected toshared storage. Client workstations receive service over the public network fromapplications running on VCS nodes. VCS monitors the nodes and their services.VCS nodes in the cluster communicate over a private network.