Active Standby Pair with Oracle TimesTen and Clusterware

An Active Standby Pair configuration includes an active database, a standby database, and optional read only subscriber databases. The standby database uses Oracle TimesTen Replication to receive the changes from the active database and forwards the changes to optional read only subscriber databases. The active and standby databases can be either TimesTen In-Memory Database or Oracle In-Memory Database Cache databases.

Oracle Clusterware is a general purpose cluster manager that manages and monitors the availability of software components that participate in a cluster. The TimesTen In-Memory Database is integrated with Oracle Clusterware via the ttCWAdmin utility. When a customer chooses to use Oracle Clusterware with the TimesTen In-Memory Database, the failover and restart of Active Standby Pair databases are handled automatically. In addition, Oracle Clusterware may be used to manage the actual applications that use TimesTen.

Install Oracle Clusterware and TimesTen

1.	Install Clusterware	Oracle Clusterware 11.1.0.7 is required.
2.	Install TimesTen	Oracle TimesTen In-Memory Database 11.2.1 is required.

This example shows how to perform the above tasks.

Configure the Active Standby Pair for Clusterware and TimesTen In-Memory Database

1.	Register cluster information	TimesTen cluster information is stored in the Oracle Cluster Registry. Register the TimesTen cluster information by executing the ttCWAdmin -ocrConfig command on any one of the hosts.
2.	Start cluster agents	Start the TimesTen cluster agents by executing the ttCWAdmin -init command on any one of the hosts. These cluster agents manage the Replication Agent and TimesTen Main Daemon on all hosts in the cluster.
3.	Create a Database	In order to set up an active standby pair configuration, you need to start with a running database. This database should include one or more tables owned by an application user. All tables must also have a primary key index. If you have an existing database, this step can be skipped.
4.	Create a user to administer the active standby pair	This database must include a user with ADMIN privilege. This user is the replication administrator responsible for managing the active standby configuration.
5.	Create cluster.oracle.ini file	The cluster.oracle.ini config file uses attributes to declaratively define the configuration of an active standby pair that will be managed by Oracle Clusterware. The entry name for the Active Standby Pair in the cluster.oracle.ini file must correspond to the system DSN created in step 2 above.
6.	Create Active Standby Pair	Create an Active Standby Pair by executing the ttCWAdmin -create command on any host.
7.	Start Active Standby Pair	Start the Active Standby Pair by executing the ttCWAdmin -start command on any host.

This example shows how to perform the above tasks.

Manage an Active Standby Pair using Clusterware and TimesTen In-Memory Database

1.	Get A/S pair status	Find the status of the Active Standby Pair via the ttCWAdmin -status command on any host in the cluster.
2.	Stop an A/S pair	Stop the Active Standby Pair via the ttCWAdmin -stop command on any host in the cluster.
3.	Drop an A/S pair	Drop the Active Standby Pair via the ttCWAdmin -drop command on any host in the cluster.
4.	Shutdown the agents	Shutdown the TimesTen cluster agents via the ttCWAdmin -shutdown command on any host in the cluster.

This example shows how to perform the above common tasks. The following link covers more admin tasks.

Automatic failover and restart for Active Standby Pairs and user applications

The following links describe how Oracle Clusterware is used to failover and restart Active Standby Pairs and user applications.
The following viewlet shows failover and failback of a user application and its corresponding Active Standby Pair and with Oracle Clusterware.