Help Center/ Relational Database Service_RDS for PostgreSQL/ User Guide/ Data Backups/ Instance-Level Backups/ Configuring Same-Region Backup Policies
Updated on 2026-03-26 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.

You do not need to set an interval for incremental backup because RDS automatically backs up incremental data every 5 minutes. Incremental backups can be used to restore data to a specific point in time.

Constraints and Billing

Table 1 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.
  • After CBR is enabled, snapshot backup is used. Existing automated and manual backups can still be used to restore data.
  • When you delete a DB instance, its automated backups are also deleted but its manual backups are retained.
  • After CBR is enabled, the next full backup is a snapshot backup. You can use the snapshot backup to restore data.

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.
  • 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 management console.
  2. Click in the upper left corner and select a region.
  3. Click in the upper left corner of the page and choose Databases > Relational Database Service.
  4. On the Instances page, click the target DB instance.
  5. In the navigation pane on the left, choose Backups & Restorations.
  6. 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 will expire on Thursday, but as it is the last backup, so it will be retained until a new backup expires. The next backup will be generated on the next Monday and will expire on the next Wednesday. So the full backup generated on Tuesday will not be automatically deleted until the next Wednesday.

    • Time Window: Set it to a one-hour period the backup will be scheduled, 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 it. Select at least one day of the week.

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