Glossary

action script

A script that defines the start, stop and check actions for a resource. The start action is invoked while starting the resource, the stop action for stopping the resource, and the check action while checking the running status of a resource.

administrator managed

Database administrators define on which servers a database resource should run, and place resources manually as needed. This is the management strategy used in previous releases.

availability directive

Instructions to Oracle Clusterware to reconfigure the system when a server leaves or joins a cluster.

cardinality

The number of servers on which a resource can run, simultaneously.

cluster

Multiple interconnected computers or servers that appear as if they are one server to end users and applications.

cluster-aware

Any application designed to be deployed using clusterware.

cluster resource

A resource that is aware of the cluster environment and subject to cross-node switchover and failover.

Cluster Time Synchronization Service

A time synchronization mechanism that ensures that all internal clocks of all nodes in a cluster are synchronized.

Cluster Verification Utility (CVU)

A tool that verifies a wide range of Oracle RAC components such as shared storage devices, networking configurations, system requirements, Oracle Clusterware, groups, and users.

CRS Administrator

A predefined Oracle Clusterware administrator role intended to control the creation of server pools. A permanent CRS Administrator is either the user (Grid user) that installed Oracle Clusterware in the Grid Infrastructure home or the system superuser (root in Linux and UNIX, and Administrator in Windows).

dependency

The relationship between two or more resources. and the interaction expressed between them.

disk group

An Oracle ASM disk group is a collection of disks that Oracle ASM manages as a unit. Within a disk group, Oracle ASM exposes a file system interface for Oracle Database files. The content of files that is stored in a disk group is evenly distributed, or striped, to eliminate hot spots and to provide uniform performance across the disks. Oracle ASM files may also be optionally mirrored within a disk group. The performance of disks in a disk group is comparable to the performance of raw devices.

Grid Infrastructure

The software that provides the infrastructure for an enterprise grid architecture. In a cluster this software includes Oracle Clusterware and Oracle ASM. For a standalone server, this software includes Oracle Restart and Oracle ASM. Oracle Database 11g release 2 (11.2) combines these infrastructure products into one software installation called the Grid Infrastructure home (Grid_home).

fixup script

Oracle Universal Installer detects when minimum requirements for installation are not completed, and creates shell script programs, called fixup scripts, to resolve many incomplete system configuration requirements. If Oracle Universal Installer detects an incomplete task, it prompts you to create a fixup script and then to run the fixup script in a separate terminal session. You can also generate fixup scripts with certain CVU commands by using the -fixup flag.

local resource

A resource that runs on the nodes of a cluster but is unaware of anything outside of the scope of the node.

OCR writer

Each crsd process also acts as an OCR server. One of the crsd processes in the cluster is the OCR server that performs I/O to the disk group or file, or block or raw device.

Oracle Automatic Storage Management (Oracle ASM)

Oracle ASM manages the storage disks used by Oracle Clusterware and Oracle RAC in disk groups. By default, Oracle Clusterware uses Oracle ASM to store OCR and voting disks.

Oracle Cluster Registry (OCR)

The Oracle RAC configuration information repository that manages information about the cluster node list and instance-to-node mapping information. OCR also manages information about Oracle Clusterware resource profiles for customized applications.

Oracle Clusterware

Software that allows groups (clusters) of connected servers to operate or be controlled as a unit.

Oracle Clusterware stack

The Oracle Clusterware stack includes Oracle Clusterware, Event Manager, Cluster Synchronization Services, and Oracle ASM (if used).

policy managed

Database administrators specify the server pool (excluding generic or free) in which the database resource runs. Oracle Clusterware places the database resource on a server.

resource

A database, application, or process managed by Oracle Clusterware.

resource state

The state of a particular resource at any given time that determines its availability to the cluster.

resource type

Defines whether a resource is either a cluster resource or a local resource.

server pool

A logical division of servers in a cluster into a group that hosts applications, databases, or both.

Single Client Access Name (SCAN)

A single name that resolves to three IP addresses in the public network.

start effort evaluation

The process that Oracle Clusterware goes through when it starts a resource. During this process, Oracle Clusterware considers resource dependencies contained in the profile of the resource.

state

A set of values that describes what the condition of a particular resource.