Automatic cleanup of expired backups

After a backup is successfully created, you can set retention policies for tenants based on your business requirements. Tenants with retention policies will trigger an automatic cleanup process every hour to ensure that expired backups are promptly deleted.

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

Considerations

• Log archive data will only be cleared after data backups are performed. Therefore, before you clear log archive data, you must make sure that backup files exist. If no backup files exist, the log archive data cannot be cleared.

• The automatic cleanup feature only supports clearing backup data and log archive data that are stored in the backup destination and archive destination specified by using the DATA_BACKUP_DEST and LOG_ARCHIVE_DEST parameters respectively. If the backup destination or archive destination is changed, the data in the original backup path or archive path cannot be cleared in the OceanBase Database.

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

• When the backup destination is an NFS mount point, the system will directly delete the backup files that meet the conditions during backup data cleanup. When the backup destination is an OSS bucket, the backup files will be 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 backup.

Configure a cleanup policy

Configure a cleanup policy in the user tenant

1. The tenant administrator of the user tenant logs in to the database.

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

   The statement is as follows:

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

   where:

   • The POLICY parameter specifies the name of the cleanup policy. Only the value default is supported. This indicates that the automatic cleanup feature applies only to backup data specified by using 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';
   

Configure a cleanup policy in the sys tenant

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

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

   The statement is as follows:

   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. Only the value default is supported. This indicates that the automatic cleanup feature applies only to backup data specified by using 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 name of the tenant for which the cleanup policy takes effect. You must specify the name of a user tenant. You can specify only one tenant name in a statement.

The following example shows how to configure a cleanup policy for the MySQL tenant, which is the sys tenant:

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

View the cleanup policies

Both system tenants and user tenants can query views to view all cleanup policies that are set.

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

2. View the cleanup policies set for the current tenant.

   • To view the cleanup policies of all tenants, query the oceanbase.CDB_OB_BACKUP_DELETE_POLICY view as a user of the system tenant.

     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
     

   • To view the cleanup policies set for the current tenant, query the oceanbase.DBA_OB_BACKUP_DELETE_POLICY view or the sys.DBA_OB_BACKUP_DELETE_POLICY view as a user of a user tenant.

     • For a MySQL tenant

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

     • For an Oracle tenant

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