Configure sparse backup for PostgreSQL - ApsaraDB RDS

ApsaraDB RDS for PostgreSQL supports sparse backup, which lets you define multi-tier retention policies instead of keeping all backup sets at a single retention period. For example, you can retain daily backups for 7 days, weekly backups for 30 days, and monthly backups for a year. By keeping only the minimum number of backup sets at each tier, sparse backup reduces storage costs and shortens restore times.

How sparse backup differs from regular backup

Dimension	Regular backup	Sparse backup
Retention flexibility	2 to 7 backup sets per week, all at one retention period. Example: one backup every Monday and Sunday, retained for 365 days.	Multiple policies with independent retention periods. Example: daily backups for 7 days, weekly for 30 days, monthly for long-term retention.
Backup set volume	Generates many backup sets over time, leading to higher storage costs.	Retains only the minimum backup sets at each tier, reducing storage usage.
Cost impact	Higher -- more backup sets stored for the full retention period.	Lower -- fewer backup sets retained at each tier.

Prerequisites

Before you begin, make sure that you have:

An RDS instance that uses cloud disks (check Storage Type on the Basic Information page)
(First-time backup users) Authorization for the service-linked role for Data Disaster Recovery (AliyunServiceRoleForDBS) through your Alibaba Cloud account. See Authorize the service-linked role for Data Disaster Recovery

Usage notes

A new sparse backup policy takes 10 to 15 minutes to take effect.
The first backup policy row is fixed and cannot be deleted. Set its backup cycle to Every Week (at least two days) or High-frequency.
If multiple policies are scheduled for the same day, only one backup set is generated. The system retains that backup set for the longest retention period among the overlapping policies.
Deleting a policy does not delete existing backup sets. They are retained for their original retention period.
If a backup fails within the backup window on a scheduled day, that day's backup is skipped. No additional backup set is retained. Failures include a failed backup job, a locked instance, or a dump that did not complete before the level-1 backup expired.

For example, if a policy backs up on the first day of each month (retained 30 days) and the backup fails on December 1, no backup set is retained for December 1.

Billing

Backup storage includes a free quota. If your total backup storage stays within the free quota, no charges apply. Storage that exceeds the quota is billed separately.

For details on the free quota and pricing, see Backup fees.

Switch to the advanced backup policy

Sparse backup requires the advanced backup policy page. If you have already switched, skip this section.

Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.
In the left-side navigation pane, click Backup and Restoration.
On the Backup and Restoration page, click the Backup Strategy tab, then click Switch to Advanced Backup Policy.

Important
If the Switch to Advanced Backup Policy button is not displayed, submit an application. After approval, refresh the page and try again.
In the confirmation dialog, select Understood and click OK.

Important
After switching, you cannot revert to the previous backup settings page.

After the switch, the Backup Strategy page displays the advanced layout shown below. You can now configure sparse backup policies.

Advanced Backup Strategy page

Configure a sparse backup policy

Add one or more backup policies with different cycles and retention periods to build a tiered retention strategy.

Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.
In the left-side navigation pane, click Backup and Restoration.
On the Backup and Restoration page, click the Backup Strategy tab and click the circled number between PostgreSQL and level-1 Backup.

In the dialog, click Add Backup Policy. Configure the policy and click OK.

Backup cycle options:

Backup cycle	Scheduling
High-frequency (15 minutes to 12 hours)	Set the interval from 15 minutes to 12 hours. To use this option, click the first row policy and change Every Week to High-frequency. For details, see High-frequency snapshot backup.
Every Week	Select one or more days of the week.
Every Month	Select one or more days of the month, or Last Day of Each Month.
Every Year	Select a specific date (for example, January 1).

You can set a different retention period for each policy. The retention period can range from 7 to 7,300 days. You can also select Long-term Retention to retain backup sets for a long term.

Note

The first row policy is fixed and cannot be deleted. Set its cycle to Every Week (at least two days) or High-frequency.
For other backup parameters, see Back up data of an ApsaraDB RDS for PostgreSQL instance.

In the lower-left corner of the Backup Strategy tab, click Save.

Configuration example

The following screenshot shows a four-tier sparse backup configuration:

Configuration example with numbered annotations

The following list describes the parameter configurations in the preceding figure:

1: Data is backed up daily. Each backup set is retained for 7 days.
2: Data is backed up every Monday. The backup set is retained for 30 days.
3: Data is backed up on the first and last day of each month. The backup set is retained for 365 days.
4: Data is backed up on January 1 of each year. The backup set is retained for long-term retention.

What to do next

View backup policies

On the Backup Strategy page, hover over the circled number to view the configured policies. The number indicates how many backup policies are configured.

View backup policies by hovering

Delete a backup policy

On the Level-1 Backup page, click the delete icon icon to remove a policy.

Note

The first row policy is fixed and cannot be deleted.

Delete a backup policy

FAQ

Can I switch back from the advanced backup policy to the regular backup settings?

No. After you switch to the advanced backup policy, the change is permanent.

What happens when multiple policies overlap on the same day?

Only one backup set is generated. The system applies the longest retention period among all overlapping policies.

What happens to backup sets if I delete a policy?

Existing backup sets are not deleted. They continue to be retained for their original retention period.