Automatic cleanup of expired backups

After a backup is successfully created, you can set a cleanup policy for the tenant based on your business needs. Tenants with a cleanup policy will trigger an automatic cleanup process every hour to ensure that expired backups are promptly removed.

The current version supports only automatic cleanup of expired backups and does not support manual cleanup of expired backups.

Considerations

• Log archive data can be cleared only after data backup is performed. Therefore, before clearing log archive data, you must make sure that data backup files exist. If no data backup files exist, the log archive data cannot be cleared.

• The automatic cleanup feature applies only to the backup destinations and log archive destinations specified in DATA_BACKUP_DEST and LOG_ARCHIVE_DEST. In the case where the backup or log archive destination is changed, data in the original backup or log archive destination cannot be cleared by using OceanBase Database.

• The automatic cleanup feature retains at least one valid backup copy. If only one valid backup copy exists, this copy will not be cleared.

• When the backup destination is an NFS mount point, the system directly deletes the eligible backup files. When the backup destination is an OSS bucket, the files are cleared based on the value of the delete_mode parameter specified for data_backup_dest or log_archive_dest. For more information, see Prepare for data backup.

Set a cleanup policy

Set a cleanup policy in a user tenant

1. Log in to the database as the tenant administrator of the user tenant.

2. Set a cleanup policy to enable the automatic cleanup feature for the tenant.

   Use the following syntax:

   obclient> ALTER SYSTEM ADD DELETE BACKUP POLICY policy_name RECOVERY_WINDOW recovery_window;
   

   where:

   • The POLICY parameter specifies the name of the cleanup policy. You can set this parameter to only default, which indicates that backup data is retained only in the locations specified in the data_backup_dest and log_archive_dest parameters.

   • The RECOVERY_WINDOW parameter specifies the time window during which the backup data can be restored. For more information about this parameter, see recovery_window.

   Here is an example:

   obclient> ALTER SYSTEM ADD DELETE BACKUP POLICY 'default' RECOVERY_WINDOW '7d';
   

Set a cleanup policy in the sys tenant

1. Log in to the sys tenant of the cluster as the root user.

2. Set a cleanup policy to enable the automatic cleanup feature for the specified user tenant.

   Use the following syntax:

   obclient> ALTER SYSTEM ADD DELETE BACKUP POLICY policy_name RECOVERY_WINDOW recovery_window TENANT tenant_name;
   

   where:

   • The POLICY parameter specifies the name of the cleanup policy. You can set this parameter to only default, which indicates that backup data is retained only in the locations specified in the data_backup_dest and log_archive_dest parameters.

   • The RECOVERY_WINDOW parameter specifies the time window during which the backup data can be restored. For more information about this parameter, see recovery_window.

   • The TENANT parameter specifies the tenant for which the cleanup policy takes effect. You can specify only one tenant name, which is the name of a user tenant.

The following example shows how to set a cleanup policy for a MySQL tenant in the sys tenant:

obclient> ALTER SYSTEM ADD DELETE BACKUP POLICY 'default' RECOVERY_WINDOW '7d' TENANT MySQL;

View the cleanup strategies that have been set

Both the system tenant and user tenants can query views to obtain all cleanup strategies that have been set.

1. Log in to the database as the tenant administrator of the system tenant or a user tenant.

2. View the cleanup strategies that have been set for the tenant.

   • The system tenant can query the oceanbase.CDB_OB_BACKUP_DELETE_POLICY view for cleanup strategies for all tenants.

     Here is an example:

     obclient> SELECT * FROM oceanbase.CDB_OB_BACKUP_DELETE_POLICY;
     +-----------+-------------+-----------------+
     | TENANT_ID | POLICY_NAME | RECOVERY_WINDOW |
     +-----------+-------------+-----------------+
     |      1002 | default     | 7d              |
     +-----------+-------------+-----------------+
     1 row in set
     

   • User tenants can query the oceanbase.DBA_OB_BACKUP_DELETE_POLICY view or the sys.DBA_OB_BACKUP_DELETE_POLICY view for cleanup strategies for the current tenant.

     • MySQL tenant

       obclient [(none)]> SELECT * FROM oceanbase.DBA_OB_BACKUP_DELETE_POLICY;
       +-------------+-----------------+
       | POLICY_NAME | RECOVERY_WINDOW |
       +-------------+-----------------+
       | default     | 7d              |
       +-------------+-----------------+
       1 row in set
       

     • Oracle tenant

       obclient [SYS]> SELECT * FROM sys.DBA_OB_BACKUP_DELETE_POLICY;
       +-------------+-----------------+
       | POLICY_NAME | RECOVERY_WINDOW |
       +-------------+-----------------+
       | default     | 7d              |
       +-------------+-----------------+
       1 row in set