Creating a Subclient for Oracle Online Backups

In some environments, it may not be possible to bring down the entire database to perform an offline backup. In such situations, you can choose online backups, where the database will be up and running during the backup. 

You can perform either a full backup or incremental backup of the Oracle database when it is online. Since full backups includes all the datafiles, tablespaces and logs, it is very time consuming, so you can plan for a full online backup less frequently (say, on weekly basis). On the other hand, incremental backups include the data and logs that have been changed since the last full backup, so they are faster and can be performed more frequently (say, on a daily basis).

If a new database object is added to the database, and if none of the subclients contain that database object, then that object is assigned to the content of the default subclient.

You can use the image copy option when you have a set of Oracle data files that are located on volumes that cannot be snapped. When you select this option, the Commvault software uses RMAN to back up the incremental database changes to a volume that can be snapped, and then takes a snap of the volume.

During the backup copy operation, the Commvault software uses the block-level interface so that you can use the data for other Oracle block-level operations, such as Copy Data Management.

If you have a UNIX configuration, you can use an ASM diskgroup for the Oracle Copy location. The location must be the base name of the ASM diskgroup, for example, +ASMDISKGROUP. You cannot use a subdirectory. If you use an ASM diskgroup for your image copy location, then the MediaAgent must have a UNIX operating system.

Best Practice: Use an online subclient when you want to create a subclient for a database that is hosted by an Amazon EC2 account.

Before You Begin

If you want to use the Oracle RMAN backup copy option by using a proxy server, you must contact Oracle for their required licensing.


  1. From the CommCell Browser, expand Client Computers > client > Oracle.
  2. Right-click the instance, point to All Tasks and then click New Subclient.

    The Creating New Subclient dialog box appears.

  3. On the General tab, in the Subclient Name box, enter a name for the subclient.
  4. On the Content tab, specify whether the backup is a full backup:
    • Select the Data check box.
    • Select the Online Database option.
  5. On the Log Backup tab, select the Backup Archive Log check box.
  6. On the Storage Device tab, from the Data Storage Policy list, select the storage policy name.
  7. Configure the IntelliSnap options.
    1. On the IntelliSnap Operations tab, select the IntelliSnap check box.

      A message appears that tells you that the next backup will be a full backup.

    2. Click OK.
    3. From the Available Snap Engines list, select the appropriate engine.

      Note: If your Oracle database is hosted by an Amazon EC2 account, you must select Amazon as the Available Snap Engine value. For information on how to manage the Amazon array, see Getting Started for Amazon.

    4. To use a proxy server, from the Use Proxy list, select the appropriate MediaAgent.

      This is the MediaAgent that is used to perform the IntelliSnap backup copy operations. For information on how to configure a proxy server for backup copy operations, see Configuring Proxy Clients for Backup Copy Operations.

      Note: When you perform an IntelliSnap backup using a proxy, make sure that the operating system on the proxy server is either the same version or later than the operating system on the client computer.

    5. To have the backup copy operation fall back to the source if the proxy is unreachable, select the Use source if proxy is unreachable check box.

      This prevents the interruption of the backup schedule when the proxy cannot be reached.

    6. To have the software create an image copy, select the Use RMAN Image Copy check box, and then in the Path box, type the full path to the image copy.

      Note: The path must have the following properties:

      • It must be a mount path that can be snapped
      • It must have enough space to store the maximum size of all the datafiles and one incremental backup.
      • If you use a file system (and not an ASM diskgroup), it must have UNIX 750 permissions
    7. Determine the copy option.

      For more information on the backup copy options, see Oracle IntelliSnap - Backup Copy.

      • To use the File system copy, select File System.
      • To use the RMAN backup copy, select RMAN.
      • To use Volume Copy, select Volume Copy (Block-Level Backup - Supports Instant Database Recovery).

        Note: You must select this option when you want to use the Copy Data Management feature.

    8. Optional: To perform an integrity check of the hardware, select the Enable Snap Integrity Check check box.
  8. Optional: Run scripts before or after the backup

    You can choose to run the post-process script even if the backup job failed.

    On the Pre/Post Process tab:

    1. In the PreBackup Process box, type the full path name for the script.
    2. In the PostBackup Process box, type the full path name for the script.
    3. To run the post backup process regardless of the job's outcome, select the Run Post Backup Process for all attempts check box.
  9. Click OK to close the Creating New Subclient dialog box.

Last modified: 5/1/2020 3:32:14 PM