A single command can be used to perform
failover. Oracle Enterprise Manager provides a Data Guard Manager GUI for setting
up, monitoring, and managing the standby database. SQL*Plus also provides an
interface for Data Guard SQL statements and initialization parameters as of Oracle
Database 11g.
The Oracle Database 10g Data Guard broker added support for creating and managing
configurations containing RAC primary and standby databases. The Data Guard
broker now leverages the Cluster Ready Services.
Possible Causes of Lost Data with a Physical Standby Database
There is a possibility that youwill lose data, even if youu se a physical standby database.
There are three possible causes of lost data in the event of primary site failure:
??? Archived redo logs have not been shipped to the standby site.
??? Filled online redo logs have not been archived yet.
??? The current online redo log is not a candidate for archiving until a log switch
occurs.
These three potential problems are addressed in different ways, as described in the
following sections.
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