To ensure a transactionally consistent state for a storage-level data snapshot, SAP HANA must first be prepared. This preparation involves the creation of an internal database snapshot. This internal snapshot freezes the database at a specific point in time, creating a consistent image. Once this internal snapshot is active, the external storage system can perform its snapshot operation. After the storage snapshot is complete, the internal database snapshot is removed, and normal database operations resume. This two-phase process guarantees that the external snapshot represents a valid and recoverable state of the database.

A. Execute the hdbbackupdiag tool.

This tool is used for checking the integrity and availability of existing backups after they have been created, not for ensuring consistency during the snapshot creation process.

B. Create a fallback snapshot.

A fallback snapshot is a specific use case for a snapshot, created before a system update to enable a quick rollback. It does not describe the underlying mechanism for ensuring consistency.

D. Trigger a savepoint.

While a savepoint is a critical part of the process to flush changed data to disk, the creation of an internal database snapshot is the specific, overarching mechanism that coordinates the entire procedure.

1. SAP HANA Administration Guide for SAP HANA Platform 2.0 SPS 07

Section: 11.3.3.1 Database Snapshots

Content: "To ensure data consistency

before a storage snapshot is created

the SAP HANA database must be prepared. Preparing the SAP HANA database for a storage snapshot involves creating an internal database snapshot. The internal database snapshot represents a consistent state of the database at a single point in time." This section explicitly states that an internal database snapshot is the mechanism for ensuring consistency.

2. SAP HANA Administration Guide for SAP HANA Platform 2.0 SPS 07

Section: 11.3.3.1.1 Creating a Storage Snapshot

Content: The guide details the workflow: "1. An SQL statement BACKUP DATA CREATE SNAPSHOT prepares SAP HANA for the storage snapshot... 2. SAP HANA creates an internal database snapshot... 3. SAP HANA freezes all write I/O operations... 4. The storage snapshot is created... 5. The storage snapshot is confirmed... 6. SAP HANA discards the internal database snapshot and resumes normal operation." This confirms that the internal snapshot (Option C) is the central mechanism.

3. SAP Note 2039883 - FAQ: SAP HANA database backup & recovery

Section: 10. Storage Snapshots

Content: The note clarifies the process: "In order to create a consistent storage snapshot

the database has to be prepared. This is done by creating a database snapshot... The database snapshot is a transactionally consistent state of the database." This reinforces that the internal database snapshot is the method to achieve consistency for the external storage snapshot.