The true incremental-forever backup feature of Database Backup allows you to use the combination of full backup and synthetic backup to reduce backup costs and resource consumption during backup.

Background information

How the true incremental-forever backup feature works:

  1. Full backup: It is Recovery Manager (RMAN) level 0 backup. All data files, archived log files, SPFILEs, and control files are backed up.
  2. Synthetic backup:
    1. Take a snapshot and mount it locally: Take a snapshot of the last full backup set or synthetic backup set, and then mount (clone) the snapshot to the local database by using FUSE.
    2. Create an incremental backup: Back up data blocks that have changed after the last full backup or synthetic backup operation and save them as an incremental backup file.
    3. Synthesize data: Execute the RMAN RECOVER COPY OF DATABASE WITH TAG 'Database Backup-specific TAG' SQL statement to read the incremental backup data in the previous step, add the incremental backup data to the full backup data, and then write (overwrite) the result as the full backup data.
      Note Synthetic backup does not affect the last full backup set.
    4. Unmount the mount point of the local database.
Note You can configure the number of backup operations each week in Database Backup. Database Backup performs a full backup operation each week. The rest are synthetic backup operations. After a full backup operation is complete, the backup set is the starting point for the synthetic backup operations of the week.
Synthetic backup provides the following advantages:
  • Fewer costs: This method backs up and stores less data and consumes less bandwidth for data transmission.
  • Lower resource consumption: Compared with full backup, synthetic backup requires less disk IOPS of the source database.
  • Backup data mounted in seconds.

Note

The true incremental-forever backup feature is in public preview. To use this feature, scan the following QR code to join the DingTalk group whose ID is 35585947.

QR code to join the DingTalk group whose ID is 35585947

For Oracle backup plans created during public preview, Backup set mode. must be Sandbox instance mount backup and the sandbox feature is enabled by default. You can create free sandbox instances for backup plans during public preview. For more information, see Overview.

Note The sandbox feature cannot be disabled during public preview.

Prerequisites

  • The Oracle database version is 11 to 19.
  • The Oracle architecture is single-instance or Oracle RAC. The Oracle Data Guard physical standby architecture is not supported.
    Note Take note of the following points when you back up an Oracle RAC database:
    • To perform a successful backup, you must check the control files, SPFILEs, data files, archived log files, and redo log files of Oracle databases before you back up the data. For more information, see Query the locations of files in an Oracle RAC environment.
    • To back up the entire RAC, you only need to deploy a backup gateway on one of the servers where the Oracle RAC database is deployed and enter the Oracle SID of the server.
  • The server where the Oracle database is located must use the Linux operating system and have a backup gateway installed. For more information, see Add a backup gateway.
  • FUSE is installed on the server.
  • The Oracle database is running in ARCHIVELOG mode. For more information, see Enable archive mode.
  • The Oracle SID is obtained. For more information, see Obtain the Oracle SID.
  • Block Change Tracking is enabled.
    Note
    1. You can execute the SQL> SELECT status FROM v$block_change_tracking; SQL statement to query whether Block Change Tracking is enabled. Block Change Tracking is disabled by default.

      ENABLED indicates that it is enabled. DISABLED indicates that it is disabled.

    2. You can execute the following SQL statement to enable Block Change Tracking:
      ALTER DATABASE ENABLE BLOCK CHANGE TRACKING USING FILE <Path of the Block Change Tracking file> REUSE;

Create a backup schedule

For more information, see Purchase a backup schedule.

Note When you purchase a backup schedule, set Database Source Type to Oracle and set Backup Method to Physical Backup.

Configure the backup schedule

  1. Log on to the DBS console.
  2. In the left-side navigation pane, click Backup Schedules. On the Backup Schedules page, select a region in the upper-left corner.
    Select a region
  3. On the Backup Schedules page, click Configure Backup Schedule in the Actions column corresponding to the backup schedule that you purchased.
  4. In the Configure Backup Source and Destination step of the Configure Backup Schedule wizard, configure the backup source and destination, and click Next in the lower-right corner of the page.
    Section Parameter Description
    N/A Schedule Name The name of the backup schedule. Database Backup generates a backup schedule name. We recommend that you set a descriptive name that makes the backup schedule easy to identify. Backup schedule names are not required to be unique.
    Backup Source Information Backup Mode The method that is used to back up data. By default, the backup method that you selected when you purchased the backup schedule is used. In this example, the physical backup mode is used.
    Instance Region The region where the instance that you want to back up is deployed.
    Backup Gateway The backup gateway on the destination server. For more information, see Add a backup gateway.
    Database Type The type of the database that you want to restore. Default value: Oracle.
    SID The SID of the destination server. For more information, see Obtain the Oracle SID.
    Oracle Home The absolute path of ORACLE_HOME. For more information, see Obtain the database program directory.
    Note This parameter is optional.
    Backup Destination Information Backup Storage Type The type of storage of the backup data. Only DBS built-in storage is supported for true incremental-forever backup.
    Storage Encryption The method used to encrypt the stored data. Valid values:
    • Encrypted: The backup data is encrypted.

      The server-side encryption feature of Object Storage Service (OSS) is used. When you upload an object to OSS, OSS encrypts and stores the object. When you download the encrypted object from OSS, OSS decrypts the object and returns the decrypted object to you. For more information, see Server-side encryption.

    • Non-encrypted: The backup data is not encrypted.
  5. In the Edit Backup Objects step, Back Up Entire Instance is automatically selected. Click Next.
    Note If you back up an entire database, the permission data and stored procedures are also backed up.
  6. In the Configure Backup Time step, set the parameters described in the following table and click Next.
    Parameter Description
    Full-scale Backup Frequency The frequency of the backup schedule. Valid values: Periodic Backup and Single Backup.
    Full Data Backup Recurrence

    The days of the week on which Database Backup runs the backup schedule.

    Note Database Backup performs a full backup operation each week. The rest are synthetic backup operations.
    Full Data Backup Start At

    The start time of the backup.

    Note If the time required to complete a full data backup is longer than the backup interval, Database Backup skips the next backup.
    Incremental log real-time backup

    Specifies whether to enable incremental backup.

    This parameter is valid only when you set Full-scale Backup Frequency to Periodic Backup.

    Maximum Concurrent Threads for Full Data Backup

    The maximum number of concurrent threads available for a full data backup. The maximum number of actual concurrent threads varies based on backup schedule specifications in the console.

    Backup network speed limit

    The limit on the network bandwidth. You can set the limit based on your need. The default value of this parameter is 0, which indicates that the network bandwidth is unlimited.

    Note When you back up the production database, we recommend that you configure throttling for backup to reduce impacts on the production database.
    Transaction Log backup interval

    The interval at which incremental backups are performed. Database Backup performs incremental backups based on your settings. If you set the interval to 10 minutes, Database Backup performs an incremental backup every 10 minutes.

    This parameter is valid only when you set the Real-Time Transaction Log Backup parameter to Enable.

    Delete Logs upon Backup Success Specifies whether to automatically delete archived log files that are backed up. Valid values:
    • Disable
    • Enable
      Note If you select Enable, you must configure the Log Retention Period parameter.
    Log Retention Period Specifies that the system will delete the log files archived before this period after a successful backup. Default value: 7 days. It indicates that the system will delete the log files archived before seven days after a successful backup.

    This parameter is valid only when the Delete Logs upon Backup Success parameter is set to Enable.

    Enable compression Specifies whether to compress data during backup. Valid values:
    • Enable: Data is compressed during backup to reduce storage space.
    • Disable: Data is not compressed during backup.
    Backup set mode Only the Sandbox instance mount backup mode is supported. Database Backup uses the RMAN tool to perform image copy backup. Backup data is streamed and sent to OSS by using the FUSE protocol, instead of being stored in disks. After the sandbox feature is enabled, the backup data can be mounted in seconds.

    You must install FUSE on your server to ensure successful backup tasks.

  7. In the Edit Lifecycle step, configure the lifecycle for a full data backup in the Configure Full Data Backup Lifecycle section.
    Note If you select Enable for the Real-Time Transaction Log Backup parameter, you must configure the backup time for incremental backup data.
  8. After the configuration is complete, click Precheck in the lower-right corner of the page.
  9. If the Precheck Passed message appears, click Start Task.
    Note When the state of the backup schedule changes to Running, the backup schedule takes effect. You can view the backup task on the Backup Schedules page. For more information, see View backup schedules.

What to do next

Database Backup allows you to restore an Oracle database to a different machine, to a different directory of the source machine, or to the same directory of the source machine. For more information, see Restore Oracle databases.