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Object Storage Service:Can I recover an OSS object after it is deleted or overwritten?

Last Updated:Mar 20, 2026

No. Once an Object Storage Service (OSS) object is manually deleted, overwritten, or removed by a configured rule, Alibaba Cloud cannot recover it. OSS backend redundancy is designed for hardware and server failure resilience — not for recovering user-initiated deletions or overwrites.

The OSS Service Terms and Service Level Agreement (SLA) define this explicitly:Service TermsService Level Agreement (SLA)

  • Service Terms: When you delete data or release a service, Alibaba Cloud deletes your data according to your instructions and does not retain it. After deletion, the data cannot be recovered. Alibaba Cloud is not obligated to retain, export, or return your data.

  • SLA: When data is deleted or your service period expires, Alibaba Cloud automatically purges the data from the disks and memory of the physical servers. The data cannot be recovered.

To protect your data, configure one or more of the protection methods described in Protect your objects from accidental deletion or overwriting before any data loss occurs.

Operations that cause irreversible data loss

The following operations permanently delete or overwrite objects. Proceed with caution.

  • Direct deletion: Deleting objects using the OSS console, ossutil, ossbrowser, or an SDK. See Delete objects.

  • Same-name upload: Uploading an object with the same name as an existing object overwrites it, regardless of the tool used (console, ossutil, ossbrowser, or SDK).

  • Lifecycle rules: If lifecycle rules are configured to delete objects that match specific criteria, OSS deletes those objects automatically. See Set up lifecycle rules.

  • Cross-region replication with deletion sync: If a cross-region replication rule uses the Sync Additions, Deletions, And Modifications policy, deletions and overwrites in the source bucket are synced to the destination bucket. See Set up cross-region replication.

  • Incorrect access permissions: If bucket permissions are misconfigured, other users may delete or overwrite your objects. See Overview of access control.

Protect your objects from accidental deletion or overwriting

All protection methods below must be configured before data loss occurs — there is no retroactive recovery option. The following table summarizes each method and when to use it.

MethodWhat it protects againstLimitation
Enable versioningAccidental deletion and same-name overwritesDoes not protect against permanent version deletion or deletion sync from cross-region replication
Use cross-region replication for backupRegional data lossUse the Sync Additions And Modifications policy only — do not use Sync Additions, Deletions, And Modifications
Configure scheduled backupObject loss when other protections are not enabledRecovery depends on the last backup time
Prevent same-name overwritesAccidental overwrites via APIApplies to API uploads only
Configure correct access permissionsUnauthorized deletion or overwritingLeast-privilege approach reduces risk but does not eliminate all human error

Enable versioning

After enabling versioning, any object that is accidentally deleted or overwritten is retained as a historical version in the bucket. Historical versions can be restored at any time.

For more information, see Overview of versioning.

Use cross-region replication for backup

Configure a cross-region replication rule with the Sync Additions And Modifications data replication policy to back up data to a bucket in a different region. This policy syncs new and modified objects but does not sync deletions, protecting your backup from accidental deletes in the source bucket.

Important

Do not use the Sync Additions, Deletions, And Modifications policy for backup purposes. That policy syncs deletions to the destination bucket, which defeats the purpose of the backup.

For more information, see Set up cross-region replication.

Configure scheduled backup

Configure the scheduled backup feature to regularly back up your objects to Cloud Backup. If objects are lost, you can promptly recover them.

For more information, see Scheduled backup.

Prevent same-name overwrites

When uploading objects via API, set the x-oss-forbid-overwrite request header to true to reject uploads that would overwrite an existing object with the same name.

Configure correct access permissions

Follow the principle of least privilege to reduce the risk of unauthorized deletion or overwriting:

  • Do not use your Alibaba Cloud account directly to access OSS.

  • For read-only services, use a Resource Access Management (RAM) user or Security Token Service (STS) temporary credentials with read-only permissions.

  • For temporary access, use STS temporary credentials instead of long-term credentials.

  • Grant each service only the minimum OSS permissions it needs.

  • Store credentials securely — do not expose your Alibaba Cloud account password or RAM user credentials.

For more information, see Overview of access control.