Use Warm standby applications to maintain a set of databases, one or more of which functions as standby copies of an active database.
As clients update the active database, Replication Server copies transactions to the standby databases, maintaining consistency between them. Should the active database fail for any reason, you can switch to a standby database, making it the active database, and resume operations with little interruption.
One method uses the multisite availability (MSA) feature to set up an active and one or more standby databases.
The second method lets you set up an active and a single standby database, both of which must be managed by the same Replication Server. This warm standby application is considered a single logical unit in a Replication Server system.
See Replication Server Administration Guide Volume 2 > Manage Warm Standby Applications to set up warm standby applications for Adaptive Server databases.
See Replication Server Heterogeneous Replication Guide > Heterogeneous Warm Standby for Oracle to set up warm standby applications for Oracle databases.