When enabling Data Guard on Exadata Database Service, the following two statements are true:
* You should use similar configurations for your Primary and Standby databases to ensure you meet the same performance service level after a role transition. This is a best practice recommended by the Oracle Maximum Availability Architecture (MAA) to avoid any performance degradation or unexpected behavior when switching roles between the primary and standby databases1. Similar configurations include the same database version, edition, shape, storage, and network settings2.
* You can enable Data Guard to support your Standby or Disaster Recovery (DR) needs with a single API call or mouse click in the Ul using cloud automation. This is one of the benefits of using Data Guard on Exadata Database Service, as it simplifies the creation and management of the standby database. You can use the Oracle Cloud Infrastructure Console, the REST API, or the CLI to enable Data Guard when creating a new database or to add Data Guard to an existing database3.
C is incorrect, because Active Data Guard does not provide read/write functionality on the standby or disaster recovery system, but read-only functionality. Active Data Guard allows you to open the standby database for read-only access while it is synchronized with the primary database, enabling real-time query and reporting on the standby database4.
D is incorrect, because you do not have to configure Data Guard manually to create the standby or DR instance for your primary Exadata Database. As mentioned above, you can use cloud automation to enable Data Guard with a single API call or mouse click in the UI3.
E is incorrect, because you can edit your configuration to change between synchronous or asynchronous transport of data to the DR site, after enabling Data Guard. You can use the Oracle Cloud Infrastructure Console, the REST API, or the CLI to modify the Data Guard association and change the protection mode, which determines the data transport method5.
References: 1: Disaster Recovery Best Practices for Exadata Database Machine using Oracle Data Guard 2: About Configuring Oracle Data Guard for Oracle Exadata Database Service on Dedicated Infrastructure 3: Using Oracle Data Guard in Exadata Cloud Service 4: About Oracle Active Data Guard 5:
Modifying a Data Guard Association