Configuring HP Serviceguard Toolkit for Oracle Data Guard

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The standby databases in a Data Guard configuration can be a combination of physical and logical
standby databases.
Active Data Guard
Active Data Guard is a new feature for Oracle 11g. Oracle Active Data Guard enhances the quality
of service by offloading resource-intensive activities from a production database to one or more
synchronized standby databases. Oracle Active Data Guard enables read-only access to a physical
standby database for queries, sorting, reporting, Web-based access, and so on, while continuously
applying changes received from the production database. Oracle Active Data Guard also enables the
use of fast incremental backups when offloading backups to a standby database, and can provide
additional benefits of high availability and disaster protection against planned or unplanned outages
at the production site.
Data Guard Broker
The Data Guard broker is a distributed management framework that automates the creation,
maintenance, and monitoring of Data Guard configurations. The broker’s interfaces improve usability
and centralize management and monitoring of the Data Guard configuration.
Role transitions
An Oracle database can be operated in one of two roles: primary or standby. Using Data Guard, the
role of a database can be changed using either a switchover or a failover operation.
Switchover
This operation allows the primary database to switch roles with one of its standby databases. There is
no data loss during a switchover. After a switchover, each database continues to participate in the
Data Guard configuration with its new role.
Failover
This operation changes a standby database to the primary role in response to a primary database
failure. If the primary database was not operating in either maximum protection mode
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or maximum
availability
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mode before the failure, some data loss may occur. If Flashback Database
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Serviceguard support for Oracle Data Guard
is enabled
on the primary database, it can be reinstated as a standby for the new primary database once the
reason for the failure is corrected.
Providing HA for ODG is essential for mission-critical business that requires ODG to be deployed in
an environment that has a wide range of applications. Integrating ODG with Serviceguard using the
toolkit has the following additional advantages:
1. Provides HA for Data Guard processes and the Data Guard broker (if used) for both primary and
the standby databases. Serviceguard has built-in monitoring capabilities to monitor system
resources like network, volume groups, and filesystems, and to initiate failover following detection.
2. Data Guard provides disaster protection and recovery only for Oracle databases. Data Guard
integration with Serviceguard Extended Distance Cluster (EDC), Metrocluster, or
Continentalclusters provides disaster protection and recovery for Oracle databases as well as for
the applications that use the databases.
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This protection mode ensures that zero data loss occurs if a primary database fails. To provide this level of protection, the redo data needed to
recover a transaction must be written to both the online redo log and to at least one synchronized standby database before the transaction
commits.
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This protection mode provides the highest level of data protection that is possible without compromising the availability of a primary database.
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Flashback Database removes the need to re-create the primary database after a failover. Flashback Database is similar to conventional
point-in-time recovery in its effects, enabling you to return a database to its state at a time in the recent past.