Help Center/ Relational Database Service_RDS for PostgreSQL/ User Guide/ Data Backups/ Introduction to Backups
Updated on 2026-07-29 GMT+08:00
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Introduction to Backups

What Are Database Backups?

RDS for PostgreSQL automatically creates backups for DB instances during the backup time window. The backups are stored based on a preset retention period (1 to 3,660 days).

A backup file is generated each time a backup is complete. If the instance fails or data is damaged, you can use the backup file to restore the instance, ensuring data reliability.

During a backup, the system reads database files, which consumes disk read I/O. Then, it compresses and uploads the backup data, which can fully utilize a single CPU core. Therefore, perform backups during off-peak hours.

In a standard Huawei Cloud environment, a full backup or restoration of 2 TB of data can be completed within 8 hours.

Backup Types

RDS for PostgreSQL supports multiple backup types. For details, see Backup Types.

Where Data Is Backed Up

  • Single-node instance

    A single-node architecture, which is more cost-effective than mainstream primary/standby DB instances. After a backup is triggered, data is backed up from the primary instance and stored as a package on OBS. The backup does not take up storage space of the instance.

  • Primary/standby instance

    An HA architecture. In a primary/standby pair, each instance has the same instance class. After a backup is triggered, data is backed up from the primary instance and stored as a package on OBS. The backup does not take up storage space of the instance.

    If a database or table in the primary instance is maliciously or mistakenly deleted, the database or table in the standby instance will also be deleted. In this case, you can only use backups to restore the deleted data.

How Data Is Backed Up

RDS for PostgreSQL automated backup is enabled by default and cannot be disabled. RDS for PostgreSQL performs automated full backups based on the time window and interval specified in the backup policy. It also backs up data changes made after the most recent automated full or incremental backup every 5 minutes. When you restore an instance to a point in time, the most recent full backup will be downloaded from OBS for restoration. After the restoration is complete, incremental backups will be replayed to the specified point in time.

Figure 1 How data is backed up

Backup Storage and Billing

Backups are saved as packages in OBS buckets.

If CBR is not enabled for your instance, the instance's backups occupy backup space in OBS. If the free space RDS provides is used up, the additional space required will be billed. For details, see How Is RDS for PostgreSQL Backup Data Billed?

If CBR is enabled, CBR snapshots are billed as follows:
  • For snapshots created before September 2025: No backup space is provided for free. You are billed for database server backup vaults in CBR on a pay-per-use basis. For details, see How Is CBR Billed?
  • For snapshots created in September 2025 and later: RDS provides free snapshot backup space. After the free space is used up, you are billed for CBR snapshots in RDS on a pay-per-use basis. For details, see RDS Pricing Details.

Deleting Backups

Backups can be deleted in different ways:
  • Manual backups can only be manually deleted.
  • Automated backups cannot be manually deleted. To delete them, set the retention period specified in your automated backup policy. Retained backups will be automatically deleted at the end of the retention period.
Parent Topic: Data Backups