Help Center/ Relational Database Service_RDS for PostgreSQL/ User Guide/ Data Backups/ Instance-Level Backups/ Configuring Same-Region Backup Policies
Updated on 2026-10-08 GMT+08:00
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Configuring Same-Region Backup Policies

Scenarios

When you create a DB instance, an automated backup policy is enabled by default. For security purposes, the automated backup policy cannot be disabled. After the DB instance is created, you can customize the automated backup policy as required and then RDS backs up data based on the automated backup policy you configure.

RDS backs up data at the DB instance level, rather than the database level. If a DB instance fails or its data is corrupted, you can restore it from backups to ensure data availability. Backups are saved as packages in OBS buckets to ensure data confidentiality and durability. Since backing up data affects database read and write performance, the automated backup time window should be set to off-peak hours.

After an automated backup policy is configured, full backups are created based on the time window and backup cycle specified in the policy. The time required for creating a backup depends on how much data there is in the instance. Backups are stored for as long as you specified in the backup policy. While a full backup is in progress, incremental backups are automatically generated every 5 minutes without manual configuration. These incremental backups can be used to restore data to a specified point in time.

This section describes how to configure the default standard backup policy, which can be supplemented with sparse backups as needed. For details, see Configuring a Sparse Backup Policy.

Differences Between Standard Backup and Sparse Backup

Table 1 Backup functions

Item

Standard Backup

Sparse Backup

Function description

RDS for PostgreSQL uses standard backup by default. A standard backup saves all data of an instance based on your chosen schedule and backup cycle. Each time a backup task finishes, the system creates a backup and stores it for the duration you specify.

Compared with the default backup policy, sparse backup reduces the backup frequency while maintaining the same retention period for the backups.

After sparse backup is enabled, a standard backup policy is displayed by default. You can add sparse backup policies as needed.

Number of backup policies

An instance has only one backup policy, which cannot be deleted.

The default policy is weekly backup. Select at least one day in a week. The backups can be retained for 1 to 3,660 days.

An instance can have only one standard backup policy and a maximum of nine sparse backup policies. The standard backup policy cannot be deleted, but the sparse backup policies can be deleted.

The standard backup policy and sparse backup policies coexist.

  • The standard backup policy is weekly backup and cannot be deleted. Select at least one day in a week. The backups can be retained for 1 to 3,660 days.
  • There are three types of sparse backup policies. The backups can be retained for 1 to 3,660 days.
    • Weekly: Select at least one day in a week.
    • Monthly: Select at least one day in a month.
    • Yearly: Select a specific day in a year.

Time window

Set it to a one-hour period within the 24-hour day during which the backup task may start, such as 01:00-02:00 or 12:00-13:00.

Set it to a one-hour period within the 24-hour day during which the backup task may start, such as 01:00-02:00 or 12:00-13:00.

Constraints and Billing

Table 2 Constraints and billing

Category

Constraints

Billing

CBR snapshot backup not enabled (physical backups by default)
  • You can only configure an automated backup policy for your DB instance, but not for read replicas.
  • When you delete a DB instance, its automated backups are also deleted but its manual backups are retained.
  • Rebooting the instance is not allowed during full backup. Exercise caution when selecting a backup time window.
  • Performing a full backup may decrease instance throughput and increase replication delay because it occupies node resources, especially disk bandwidth.

Backups are saved as packages in OBS buckets. For the billing details, see How Is RDS for PostgreSQL Backup Data Billed?

CBR snapshot backup enabled
  • You can only configure an automated backup policy for your DB instance, but not for read replicas.
  • CBR snapshot backups depend on the Cloud Backup and Recovery (CBR) service. For details, see What Is CBR?
  • Enabling CBR snapshot backup will incur fees. CBR snapshot backups are billed by actual vault usage, which is calculated by CBR.
  • The backup time is proportional to how much data your instance has. Too much data can decrease the backup efficiency. If you have large amounts of data and want to speed up the backup process, enable CBR snapshot backup.
  • After CBR snapshot backup is enabled, the backup method is snapshot backup. Existing automated and manual backups can still be used to restore data.
  • After CBR snapshot backup is enabled, deleting an instance automatically deletes its automated backups, while manual backups are retained.
  • After CBR snapshot backup is enabled, the next full backup is a snapshot backup. You can use the snapshot backup to restore data.

If CBR is enabled, CBR snapshot backups 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.
  • For an instance with CBR snapshot backup enabled, its snapshot backups retained in the recycle bin after the instance is deleted will be billed based on the CBR backup billing rules within the retention period.

Viewing or Modifying an Automated Backup Policy

  1. Log in to the RDS console.
  2. Click in the upper left corner and select a region.
  3. On the Instances page, click the target DB instance.
  4. In the navigation pane on the left, choose Backups & Restorations.
  5. In the upper right corner of the page, choose Modify Backup Policy > Configure Same-Region Backup Policy. On the displayed page, you can view the backup policies you have. If you want to modify one of them, adjust the following parameters:

    Figure 1 Modifying a backup policy
    • Retention Period: How many days your automated full backups and incremental backups can be retained. The retention period is from 1 to 3,660 days, with a default of 7 days.
      • Extending the retention period enhances data availability.
      • Reducing the retention period takes effect for existing backups. Any backups (except manual backups) that have expired will be automatically deleted. Exercise caution when performing this operation.

      Automatic deletion policy for full backups:

      To ensure data integrity, the system keeps the most recent backup that has exceeded the retention period during automatic deletions. This ensures that data within the retention period can still be restored.

      For example, if Backup Cycle was set to Monday and Tuesday and Retention Period was set to 2, the deletion behavior is as follows:

      • The full backup created on Monday is automatically deleted on Thursday.

        The full backup created on Monday expires on Wednesday, but according to the deletion policy, the system retains the most recent full backup that has exceeded the retention period. So it is retained until a new backup expires. The next full backup is created on Tuesday and expires on Thursday. Therefore, on Thursday, the Monday backup is deleted and the Tuesday backup is retained.

      • The full backup created on Tuesday is automatically deleted on Wednesday of the following week.

        The backup generated on Tuesday is scheduled to expire on Thursday; however, as it is the last available backup, it is retained until a subsequent backup expires. The next backup is generated the following Monday and expires the following Wednesday, at which point the full backup generated on Tuesday is automatically deleted.

    • Time Window: Set it to a one-hour period within the 24-hour day during which the backup task may start, such as 01:00-02:00 or 12:00-13:00. It indicates when the backup starts, not the duration of the entire backup task. The backup duration depends on the data volume of your instance.

      To minimize potential impact on workloads, set the time window to off-peak hours. The backup time is in UTC format. The backup time window changes with the time zone if the DST or standard time is switched.

    • Backup Cycle: All options are selected by default, but you can change them. Select at least one day of the week.
    • Enable Standby Backup: For primary/standby instances that use physical backups, you can enable standby backup. Backup tasks will be offloaded to standby nodes, reducing the load on primary nodes.

  6. Click OK.
Parent Topic: Instance-Level Backups