Ensure that you meet the requirements for using Oracle Exadata Database Service on Exascale Infrastructure with Oracle Data Guard.

Ensure that your environment meets the following network requirements:

• The primary and standby databases can be part of VM clusters in different compartments.

• The primary and standby databases must, however, be part of the same VCN within the same region.

• If you want to configure Oracle Data Guard across regions, then you must configure remote virtual cloud network (VCN) peering between the primary and standby databases. Networking is configured on the cloud VM cluster resource.

  For Exadata Data Guard configurations, OCI supports the use of hub-and-spoke network topology for the VCNs within each region. This means that the primary and standby databases can each utilize a "spoke" VCN that passes network traffic to the "hub" VCN that has a remote peering connection. See Transit Routing inside a hub VCN for information on setting up this network topology.

• To set up Oracle Data Guard within a single region, both Oracle Exadata Database Service on Exascale Infrastructure instances must use the same VCN. When setting up Data Guard within the same region, Oracle recommends that the instance containing the standby database be in a different availability domain from the instance containing the primary database to improve availability and disaster recovery.

• Configure the ingress and egress security rules for the subnets of both Oracle Exadata Database Service on Exascale Infrastructure instances in the Oracle Data Guard association to enable TCP traffic to move between the applicable ports. Ensure that the rules you create are stateful (the default).

  For example, if the subnet of the primary Oracle Exadata Database Service on Exascale Infrastructure instance uses the source CIDR 10.0.0.0/24 and the subnet of the standby instance uses the source CIDR 10.0.1.0/24, then create rules as shown in the subsequent example.

Ingress Rules:

						Stateless: No
						Source: 10.0.1.0/24 
						IP Protocol: TCP 
						Source Port Range: All 
						Destination Port Range: 1521
						Allows: TCP traffic for ports: 1521

						Egress Rules:


						Stateless: No
						Destination: 10.0.1.0/24 
						IP Protocol: TCP 
						Source Port Range: All
						Destination Port Range: 1521
						Allows: TCP traffic for ports: 1521
					

Ingress Rules:

						Stateless: No
						Source: 10.0.0.0/24 
						IP Protocol: TCP 
						Source Port Range: All 
						Destination Port Range: 1521
						Allows: TCP traffic for ports: 1521

						Egress Rules:

						Stateless: No
						Destination: 10.0.0.0/24 
						IP Protocol: TCP 
						Source Port Range: All
						Destination Port Range: 1521
						Allows: TCP traffic for ports: 1521
					

For information about creating and editing rules, see Security Lists .

For Data Guard operations to work, the SYS password and the TDE wallet password of the primary and standby databases must all be the same.

If you change any one of these passwords, you must update the rest of the passwords to match. See Changing the Database Passwords to learn how to change the SYS password or the TDE wallet password.

If you make any change to the TDE wallet (such as adding a master key for a new PDB or changing the wallet password), you must copy the wallet from the primary to the standby so that Data Guard can continue to operate. For Oracle Database versions earlier than 12.2, if you change the SYS password on one of the peers, you need to manually sync the password file between the DB systems.

Possible TDE key replication issue, and MRP and DG LCM operation failures.

KMS RPM libkmstdepkcs11_1.286-1.286-1-Linux.rpm is the latest available which supports active replication of key between cross-region KMS vaults (source and target), and it is recommended to upgrade the RPM on clusters participating in Data Guard. OCI Vault cross-region Data Guard works with a lower version of RPM, but the older version does not guarantee active replication of keys. If the TDE keys have any replication issue between vaults, Data Guard replication might have an impact (MRP fails on standby cluster due to missing key on target vault) and MRP could resume only after the keys are replicated to the target vault. To avoid MRP and DG LCM operation failures, upgrade the libkms RPM on both the clusters, and restart the databases (only databases using customer-managed keys).

If node addition is done either on the standby database or the primary database, the metadata must be updated manually on the database other than the one where the node was added.

When adding a node to a VM cluster, an instance of the Data Guard database is automatically created on the new node. However, metadata updation on the remote database, that is, the primary database if addition is done on the standby database and vice versa, must be done manually.

This can be done by copying over the addinstance JSON file, /var/opt/oracle/dbaas_acfs/<dbname>/addInstance.json created at the end of instance addition and running the /var/opt/oracle/ocde/rops update_instance <dbname> <path to addInstance JSON> command on any node of the remote cluster.

If node removal is done either on the standby database or the primary database, the metadata must be updated manually on the database other than the one where the node was removed.

When removing a node from a VM cluster, the instance and it's metadata on the removing node is deleted automatically. However, deletion of the corresponding metadata on the remote database, that is, the primary database if removal is done on the standby database and vice versa, must be done manually.

This can be done by running the /var/opt/oracle/ocde/rops remove_instance <dbname> <Instance Name> command on any node of the remote cluster.

A switchover reverses the primary and standby database roles.

Each database continues to participate in the Data Guard association in its new role. A switchover ensures no data loss. You can use a switchover before you perform planned maintenance on the primary database. Performing planned maintenance on a Exadata database virtual machine with a Data Guard association is typically done by switching the primary to the standby role, performing maintenance on the standby, and then switching it back to the primary role.

With Oracle Data Guard, a failover transitions the standby database into the primary role after the existing primary database fails or becomes unreachable.

A failover might result in some data loss when you use Maximum Performance protection mode.

The reinstate command reinstates a database into the standby role in an Oracle Data Guard association.

You can use the reinstate command to return a failed database into service after correcting the cause of failure.

Learn how to enable Data Guard association between databases.

1. Open the navigation menu. Under Oracle Database, click Exadata Database Service on Exascale Infrastructure.
2. Choose your Compartment that contains the Oracle Exadata Database Service on Exascale Infrastructure instance with the database for which you want to enable Oracle Data Guard..
3. Navigate to the cloud VM cluster that contains a database you want to assume the primary role:
4. Under Exadata Database Service on Exascale Infrastructure, click Exadata VM clusters. In the list of VM clusters, find the VM cluster that you want to access and click its highlighted name to view the details page for the cluster.
5. On the VM cluster details page, in the Databases section, click the name of the database that you want to make primary.
6. On the Database Details page, under Resources, click Data Guard Associations.
7. In the Data Guard Associations section, click Enable Data Guard.
8. On the Enable Data Guard page, configure your Data Guard association.

   • In the Select VM Cluster section, provide the following information for the standby database to obtain a list of available Exadata systems in which to locate the standby database:

     • Region: Select a region where you want to locate the standby database. The region where the primary database is located is selected, by default. You can choose to locate the standby database in a different region. The hint text associated with this field tells you in which region the primary database is located.
     • Availability domain: Select an availability domain for the standby database. The hint text associated with this field tells you in which availability domain the primary database is located.

     • Data Guard peer resource type: Select VM Cluster.

       Select a VM cluster from the drop-down list.

   • Data Guard association details

     • Data Guard Type: Select Active Data Guard or Data Guard. Active Data Guard provides additional features including: Real-Time Query and DML Offload, Automatic Block Repair, Standby Block Change Tracking, Far Sync, Global Data Services, and Application Continuity. Note that Active Data Guard requires an Oracle Active Data Guard license. For more information on Active Data Guard, see Active Data Guard. For a complete overview of both Data Guard types, see Introduction to Oracle Data Guard.

     • Protection mode: The protection mode can be Maximum Performance or Maximum Availability. See Oracle Data Duard Protection Modes for information on these options.

     • Transport type: The redo transport type used for this Data Guard association.

       See Redo Transport Services for information on these options.
   • In the Choose Database Home section, choose one of the following:

     • Select an existing Database Home: If you use this option, select a home from the Database Home display name drop-down list.

     • Create a new Database Home: If you choose this option, enter a name for the new Database Home in the Database Home display name field. Click Change Database Image to select a database software image for the new Database Home. In the Select a Database Software Image panel, do the following:
       1. Select the compartment containing the database software image you want to use to create the new Database Home.
       2. Select the Oracle Database software version that the new Database Home will use, then choose an image from the list of available images for your selected software version.
       3. Click Select.
       Note
       
       Oracle recommends applying the same list of patches to the Database Homes of the primary and standby databases.
   • In the Configure standby database: section, provide standby database details.
     Note
     
     You cannot modify the db_unique_name and SID prefix after creating the database.

     • Database unique name: Optionally, specify a value for the DB_UNIQUE_NAME database parameter. This value must be unique across the primary and standby cloud VM clusters. The unique name must meet the requirements:

       • Maximum of 30 characters
       • Contain only alphanumeric or underscore (_) characters
       • Begin with an alphabetic character
       • Unique across the VM cluster. Recommended to be unique across the tenancy.
       If not specified, the system automatically generates a unique name value, as follows:

       <db_name>_<3_chars_unique_string>_<region-name>

     • Database password: Enter the database administrator password of the primary database. Use this same database administrator password for the standby database.

       Note
       
       The administrator password and the TDE wallet password must be identical. If the passwords are not identical, then follow the instructions in Changing the Database Passwords to ensure that they are.
9. Optional. Enable thin clone: Select this option to leverage Exascale redirect-on-write technology to create a thin clone of the PDB. This option results in the reuse of duplicate blocks with the parent PDB, shared with the clone. Deselecting this option results in a traditional, full clone with all blocks copied, and fully independent from the parent.
10. Click Show Advanced Options to specify advanced options for the standby database:

    • Management:

      Oracle SID prefix: The Oracle Database instance number is automatically added to the SID prefix to create the INSTANCE_NAME database parameter. The INSTANCE_NAME parameter is also known as the SID. If not provided, then the SID prefix defaults to the first 12 characters of the db_unique_name.

      The SID prefix must meet the requirements:

      • Maximum of 12 characters
      • Contain only alphanumeric characters
      • Begin with an alphabetic character
      • Unique in the VM cluster and across primary and standby databases
11. Click Enable Data Guard. When you create the association, the details for a database and its peer display their respective roles as Primary or Standby.

• View Data Guard Provisioning Progress
  View the progress of Data Guard Provisioning tasks using the Work Requests page.

To view the role of each database in a Data Guard association in an Cloud VM Cluster, follow this procedure.

1. Open the navigation menu. Under Oracle Database, click Exadata Database Service on Exascale Infrastructure.
2. Choose your Compartment.
3. Navigate to the cloud VM cluster that contains the databases you wish to view their roles in Data Guard associations.
4. In the Databases section under Resources, the role of each database in this VM Cluster is indicated in the Data Guard role column.

Learn to enable automatic backups on a standby database.

1. Open the navigation menu. Under Oracle Database, click Exadata Database Service on Exascale Infrastructure.
2. Choose your Compartment that contains the Exadata Cloud Infrastructure instance with the database for which you want to enable automatic database.
3. Navigate to the cloud VM cluster or DB system that contains the primary database. Under Oracle Exadata Database Service on Exascale Infrastructure, click Exadata VM clusters. In the list of VM clusters, find the VM cluster you want to access and click its highlighted name to view the details page for the cluster.
4. On the VM cluster page, in the Databases section, click the name of the primary database.
5. On the Database Details page, under Resources, click Data Guard Associations.
6. Click the name of the standby database for which you want to enable automatic backups.

   The system displays a banner if automatic backups are not enabled for this database.

7. Click Enable automatic backups on the banner.
8. On the resulting Configure Automatic Backups window, enter the following details:
   • Enable automatic backup: Check the check box to enable or disable automatic incremental backups for this database. If your database is in a security zone compartment, you must enable automatic backups.
   • Backup Scheduling:
     • Full backup scheduling day: Choose a day of the week for the initial and future L0 backups to start.
     • Full backup scheduling time (UTC): Specify the time window when the full backups start when the automatic backup capability is selected.
     • Take the first backup immediately: A full database backup includes all datafiles, control file, and parameter files associated with the target database. Archive backups are separate and decoupled and executed every 30 minutes. You can choose to execute the first full backup immediately or defer to the assigned full backup scheduling time. If you defer to the latter, the database will not be recoverable until the first backup completes.
   • Backup Destination: Object Storage is selected by default and you cannot change it.
     Note
     
     

     • If automatic backup is enabled on the primary database and the backup destination is Autonomous Recovery Service, then you cannot enable backup on the standby database.
     • If automatic backup is enabled on the primary database and the backup destination is Object Storage, then you can enable backup on the standby database. Note that you can only select Object Storage as the backup destination.
     • If automatic backup is disabled on the primary database, you can still enable backup on the standby database by selecting Object Storage as the backup destination.
9. Click Save Changes.

You initiate a switchover operation by using the Data Guard association of the primary database.

1. Open the navigation menu. Click Oracle Database, then click Exadata Database Service on Exascale Infrastructure
2. Choose the Compartment that contains the Oracle Exadata Database Service on Exascale Infrastructure instance with the database for which you want to enable Oracle Data Guard.

3. Navigate to the cloud VM cluster or DB system that contains the Data Guard association:

   Oracle Exadata Database Service on Exascale Infrastructure, click Exadata VM Clusters. In the list of VM clusters, find the VM cluster you want to access and click its highlighted name to view the details page for the cluster.

4. Under Resources, click Data Guard Associations.
5. For the Data Guard association on which you want to perform a switchover, click the Actions icon (three dots), and then click Switchover.

6. In the Switchover Database dialog box, enter the database admin password, and then click OK.

   This database should now assume the role of the standby, and the standby should assume the role of the primary in the Data Guard association.

You edit the Oracle Data Guard association to configure the Data Guard protection for the primary database.

1. Open the navigation menu. Click Oracle Database, then click Exadata Database Service on Exascale Infrastructure
2. Choose the Compartment that contains the Exadata Cloud Service instance with the database for which you want to enable Oracle Data Guard.

3. Navigate to the cloud VM cluster or DB system that contains the Data Guard association:

   Under Oracle Exadata Database Service on Exascale Infrastructure, click Exadata VM Clusters. In the list of VM clusters, find the VM cluster you want to access and click its highlighted name to view the details page for the cluster.

4. Under Resources, click Data Guard Associations.
5. For the Data Guard association you want to manage, click the Actions menu (
   
   
   
   ), and then click Edit Protection Mode.

6. In the Edit Data Guard Association panel, configure the Data Guard association:

   • Data Guard Type: Select Active Data Guard or Data Guard. Active Data Guard provides additional features including: Real-Time Query and DML Offload, Automatic Block Repair, Standby Block Change Tracking, Far Sync, Global Data Services, and Application Continuity. Note that Active Data Guard requires an Oracle Active Data Guard license. For more information on Active Data Guard, see Active Data Guard. For a complete overview of both Data Guard types, see Introduction to Oracle Data Guard
   • Protection mode: The protection mode can be Maximum Performance or Maximum Availability. See Oracle Data Guard Protection Modes for information on these options.

   • Transport type: The redo transport type used for this Oracle Data Guard association.

   • Database admin password: Enter the ADMIN password for the database.
7. Click Save.

You initiate a failover operation by using the Data Guard association of the standby database.

1. Open the navigation menu. Click Oracle Database, then click Exadata Database Service on Exascale Infrastructure
2. Choose the Compartment that contains the Oracle Exadata Database Service on Exascale Infrastructure instance with the database for which you want to enable Oracle Data Guard.

3. Navigate to the cloud VM cluster that contains the Data Guard association:

   Under Oracle Exadata Database Service on Exascale Infrastructure, click Exadata VM Clusters. In the list of VM clusters, find the VM cluster you want to access and click its highlighted name to view the details page for the cluster.

4. Under Resources, click Data Guard Associations.
5. For the Data Guard association on which you want to perform a failover, click Failover.

6. In the Failover Database dialog box, enter the database admin password, and then click OK.

   This database should now assume the role of the primary, and the old primary's role should display as Disabled Standby.

1. Open the navigation menu. Click Oracle Database, then click Exadata Database Service on Exascale Infrastructure
2. Choose the Compartment that contains the Oracle Exadata Database Service on Exascale Infrastructure with the database for which you want to enable Oracle Data Guard.

3. Navigate to the cloud VM cluster or DB system that contains the Data Guard association:

   Under Oracle Exadata Database Service on Exascale Infrastructure, click Exadata VM Clusters. In the list of VM clusters, find the VM cluster you want to access and click its highlighted name to view the details page for the cluster.

4. Under Resources, click Data Guard Associations.
5. For the Data Guard association on which you want to reinstate this database, click the Actions icon (three dots), and then click Reinstate.

6. In the Reinstate Database dialog box, enter the database admin password, and then click OK.

   This database should now be reinstated as the standby in the Data Guard association.

On an Oracle Exadata Database Service on Exascale Infrastructure instance, you remove a Data Guard association by terminating the standby database.

1. Open the navigation menu. Click Oracle Database, then click Exadata Database Service on Exascale Infrastructure.
2. Choose the Compartment that contains the Oracle Exadata Database Service on Exascale Infrastructure VM cluster with the database for which you want to enable Oracle Data Guard.

3. Navigate to the cloud VM cluster that contains the standby database:

   Under Oracle Exadata Database Service on Exascale Infrastructure, click Exadata VM Clusters. In the list of VM clusters, find the VM cluster that you want to access, and click its highlighted name to view the details page for the cluster.

4. For the standby database you want to terminate, click the Actions icon (
   
   
   
   ), and then click Terminate.

5. In the Terminate Database dialog box, enter the name of the database, and then click OK.