What is soft delete in Azure Storage blob?

When soft delete for blobs is enabled on a storage account, you can recover objects after they have been deleted, within the specified data retention period. This protection extends to any blobs (block blobs, append blobs, or page blobs) that are erased as the result of an overwrite.

If data in an existing blob or snapshot is deleted while blob soft delete is enabled but blob versioning is not enabled, then a soft deleted snapshot is generated to save the state of the overwritten data. After the specified retention period has expired, the object is permanently deleted.

If blob versioning and blob soft delete are both enabled on the storage account, then deleting a blob creates a new version instead of a soft-deleted snapshot. The new version is not soft-deleted and is not removed when the soft-delete retention period expires. Soft-deleted versions of a blob can be restored within the retention period by calling the Undelete Blob operation. The blob can subsequently be restored from one of its versions by calling the Copy Blob operation. For more information about using blob versioning and soft delete together, see Blob versioning and soft delete.

Soft deleted objects are invisible unless explicitly listed.

Blob soft delete is backwards compatible, so you don't have to make any changes to your applications to take advantage of the protections this feature affords. However, data recovery introduces a new Undelete Blob API.

Blob soft delete is available for both new and existing general-purpose v2, general-purpose v1, and Blob storage accounts. Both standard and premium account types are supported. Blob soft delete is available for all storage tiers including hot, cool, and archive. Soft delete is available for unmanaged disks, which are page blobs under the covers, but is not available for managed disks.