1.2 Configurations to which HA Monitor Kit can be applied

To guard against system failures, HA Monitor employs two systems, using one to execute jobs and keeping the other as a standby. These systems are called hosts. A program that executes jobs on a system (host) is called a server. HA Monitor performs hot standby on a server-by-server basis.

This section explains the available Oracle system configurations, Oracle component configurations, and hot-standby configurations, which the reader needs to know when using HA Monitor Kit.

Organization of this section
(1) Oracle system configurations
(2) Oracle component configuration
(3) Hot-standby configuration

(1) Oracle system configurations

Some Oracle system configurations can be made into hot-standby configurations by using HA Monitor Kit while others cannot, as described below.

Configurations with which HA Monitor Kit can be used
You can use HA Monitor Kit with an Oracle single-configuration system (a system that has the primary database only) and with an Oracle system configuration that has a primary database that is configured with a redundant database for disaster recovery to protect the database against disasters. The following figures show examples of these configurations.

Figure 1-2 Configuration in which HA Monitor Kit can be used (Oracle single configuration)

[Figure]

Figure 1-3 Configuration in which HA Monitor Kit can be used (primary database with disaster recovery configuration)

[Figure]
Configuration in which HA Monitor Kit cannot be used
You cannot use HA Monitor Kit with a RAC configuration (one that uses an Oracle RAC). The following figure shows an example of a RAC configuration.

Figure 1-4 Configuration to which HA Monitor Kit cannot be used (RAC configuration)

[Figure]

(2) Oracle component configuration

When HA Monitor Kit is installed on a system, it treats Oracle instances and Oracle listeners as servers that are subject to hot standby. An Oracle instance is a combination of shared memory and processes, and is associated with a database as a component necessary for the client to continue jobs. An Oracle listener is a component that relays a request from the client to an Oracle instance. Both Oracle instances and the Oracle listener that manages these instances must be running on the same system.

The following figure shows an Oracle component configuration.

Figure 1-5 Oracle component configuration

[Figure]

HA Monitor Kit can manage Oracle instances and Oracle listeners as separate servers, or can group multiple such components into a single server for management purposes. For details, see 3.1.1 Oracle component configuration and hot standby switchable unit considerations.

(3) Hot-standby configuration

You use HA Monitor Kit in a hot-standby configuration supported by HA Monitor. Determine which hot-standby configuration you can use based on the version of HA Monitor you are using. For details about the hot-standby configurations of HA Monitor, see the descriptions about hot-standby configurations in the manual HA Monitor (for Linux(R)).

In a hot-standby configuration of HA Monitor, servers are operated in either the server mode or monitor mode. In a configuration in which HA Monitor Kit is used, Oracle servers are operated in the monitor mode.