Scheduling a Shutdown of Active Standby Pair With AWT Cache Groups

When you are using active standby pairs with AWT cache groups, the environment includes both an active and a standby master, potentially one or more subscribers, and at least one Oracle Database.

The following is the recommended method when you initiate a scheduled shutdown of outstanding transactions in this environment. This order of events provides the time needed to finish applying outstanding transactions before shut down and minimizes the time needed to restart all components.

1. Shut down all applications.

2. Ensure that all transactions have propagated to the Oracle database.

3. Shut down TimesTen.

4. Shut down the Oracle Database.

Then, when you are ready to restart all components:

1. Restart the Oracle Database.
2. Restart TimesTen.
3. Restart any applications.

You can shut down all of these products in any order without error. The order matters only to maximize performance and reduce the need for preserving unapplied transactions. For example, when you are using AWT cache groups within the active standby pair and if you shut down the Oracle database before TimesTen, then all unapplied transactions accumulate in the TimesTen transaction logs. Thus, when you restart TimesTen and Oracle, you could potentially have a lower throughput while pending transactions are applied to the Oracle database. Thus, shutting down TimesTen before the Oracle database provides the most efficient method for your scheduled shutdown and startup. In addition, shutting down the applications before TimesTen stops any additional requests from being sent to an unavailable TimesTen database.