This illustration shows node failure in dedicated server environments.

The primary instance is SALES1 and the secondary instance is SALES2.

1. The client requests a connection to the primary instance's listener, but the primary instance (SALES1) fails.
2. The client requests a re-connection from the primary instance, but is rejected.
3. The secondary instance (SALES2) becomes the primary instance, allowing the client to re-establish the connection to the new primary instance.