9.2 Cluster Terminology

The following terminology is used in this section when discussing the cluster environment:

  • Active node: The cluster server that currently owns the cluster resource and responds to network requests made to shared volumes on that resource.

  • Passive node: The cluster server that does not currently own the cluster resources but is available if the resource fails over or is migrated to it.

  • Active/Passive clustering: The cluster includes active nodes and passive nodes. The passive nodes are used if an active node fails.

  • Virtual server: A cluster-enabled pool and related services that appears to clients as a physical server but is not associated with a specific server in the cluster. This is the name of the virtual server as it appears to NCP and Linux clients.

  • CIFS virtual server: A cluster-enabled pool and the CIFS service that appear to CIFS clients as a physical server, but are not associated with a specific server in the cluster. This is the name of the virtual server as it appears to CIFS clients.

  • Cluster Resource IP address: Each cluster-enabled NSS pool requires its own static IP address. The IP address is used to provide access and failover capability to the cluster-enabled pool (virtual server). The IP address assigned to the pool remains assigned to the pool regardless of which server in the cluster is active.

  • Load script: A file that contains the cluster resource definition and commands that load services and load the NSS pool and its volumes for a given cluster resource. Load scripts are generated by default when you cluster-enable a pool, and are modified by using the Clusters plug-in for Cluster Services.

  • Monitor script: A file that contains the cluster resource commands that allows Cluster Services to detect when an individual resource on a node has failed independently of its ability to detect node failures. The script is generated by default, but monitoring for a resource is not enabled by default. For information about how to enable and configure monitoring for a resource, see Enabling Monitoring and Configuring the Monitor Script in the OES Cluster Services for Linux Administration Guide.

  • Unload script: A file that contains the cluster resource definition and commands that unload services and dismount the NSS pool and its volumes for a given cluster resource. Unload scripts are generated by default when you cluster-enable a pool, and are modified by using the Clusters plug-in for Cluster Services.