Preparations for secondary backup

This topic describes how to configure the destination for a secondary backup, backup parameters, and secondary backup parameters before you perform a secondary backup.

Configure the destination for a secondary backup

Before you perform a secondary backup, you can configure the destination for a secondary backup operation by using the backup_backup_dest parameter. OceanBase Database allows you to use Network File System (NFS) and Object Storage Service (OSS) as the destination for the secondary backup.

1. Log on to the sys tenant as the root user.

2. Configure the destination for secondary backup.

   The setting method of the backup_backup_dest parameter is the same as that of the backup_dest parameter. For more information about the setting of the backup_dest parameter, see Preparations for backup.

   Notice

   • Before you set backup_backup_dest, ensure that backup_dest is set.

   • The destination specified in backup_backup_dest must be different from that specified in backup_dest.

   Here are the examples:

   • NFS

     Notice

     When you use NFS as the destination for the secondary backup, note the following points:

     • The value of backup_backup_dest cannot be a string with a question mark (?).

     • We recommend that you set backup_backup_dest to an absolute path to ensure that the OBServer node has the write permission on backup_backup_dest.

     • Ensure that all OBServer nodes are mounted to NFS of the same server and use the parameter settings recommended in this topic. For more information about the procedure of mounting NFS, see Deploy the NFS client.

     Set the backup destination to NFS:

     obclient> ALTER SYSTEM SET backup_backup_dest='file:///data/nfs/backup_backup';
     

   • OSS

     Set the destination for the secondary backup to OSS and configure a clearing mode:

     obclient> ALTER SYSTEM SET backup_backup_dest='oss://oceanbase-test-bucket/backup_backup/?host=xxx.aliyun-inc.com&access_id=xxx&access_key=xxx&delete_mode=delete';
     

After the destination for the secondary backup is configured, you can replace the destination after performing the following operation during a secondary backup task:

• Stop the secondary backup task.

  For more information, see Stop a secondary backup task.

• Recommended. Stop secondary backup clearing.

  For more information, see Stop secondary backup clearing.

(Optional) Configure backup parameters

Before you perform a secondary backup, if you want two copies of all backup set pieces, you must set the copies of the backup set by configuring the backup_copies parameter for backup_dest_option.

1. Log on to the sys tenant as the root user.

2. Configure the backup_copies parameter for backup_dest_option.

   The backup_dest_option parameter specifies backup-related parameters. The backup_copies parameter specifies the number of backup copies. The value range of this parameter is [0, 8] and the default value is 0. If the value of backup_copies is set to a value less than 2, the result of the secondary backup task does not affect the backup clearing task. If backup_copies=2, the source backup data can be cleared only when the secondary backup is successful. If secondary backup is not set, we recommend that you use the default value.

   For more information about the configuration and description of the backup_copies parameter for backup_dest_option, see Preparations for backup.

   For more information about the backup_dest_option parameter, see backup_dest_option.

(Optional) Configure secondary backup parameters

1. Log on to the sys tenant as the root user.

2. Set the backup_backup_dest_option parameter to configure parameters related to secondary backup.

   You can set the following secondary backup-related parameters for backup_backup_dest_option:

   • log_archive_checkpoint_interval

     The log_archive_checkpoint_interval parameter specifies the interval of secondary log backup operations when log splitting is not enabled.

     If you do not specify this parameter, the value of the cluster-level log_archive_checkpoint_interval is used. If you do not specify either backup_backup_dest_option or log_archive_checkpoint_interval, the default value 0 is used.

     We recommend that you enable log splitting to start a secondary log backup.

   • recovery_window

     The recovery_window parameter specifies the time window for restoring secondary backup data. The system determines whether secondary backup data has expired based on the value of this parameter. For example, the configuration recovery_window='7d' indicates that backup data within the last 7 days can be restored, and the secondary backup data beyond this restore window is considered expired. For more information about the recovery_window parameter, see Automatically clear backup data for clusters.

     If you do not specify the parameter in this parameter, the value of the cluster-level parameter backup_recovery_window is used by default. If you do not specify either backup_backup_dest_option or backup_recovery_window, the default value 0 is used, which indicates that secondary backup data does not expire.

   • auto_delete_obsolete_backup

     The auto_delete_obsolete_backup parameter specifies whether to automatically clear expired secondary backup data. For example, auto_delete_obsolete_backup=true specifies that expired secondary backup data is automatically cleared.

     If you do not specify this parameter, the value of the cluster-level parameter auto_delete_expired_backup is used by default. If you do not specify either backup_backup_dest_option or auto_delete_expired_backup, the default value false is used, indicating that expired secondary backup data will not be automatically cleared.

     For example:

     obclient> ALTER SYSTEM SET backup_backup_dest_option='recovery_window=14d&auto_delete_obsolete_backup=true';
     

     For more information about the backup_backup_dest_option parameter, see backup_backup_dest_option.