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With SQL Server 2022, Microsoft introduced a feature called Ledger that allows database tables to be examined for tampering. This functionality is based on blockchain technology and creates a ledger table of data hash values that are stored in a blockchain. This ledger digest and its verification can then be stored on a WORM storage device. This allows organizations to comply with data storage requirements such as SEC rule 17a-4(f) which address unauthorized data tampering and/or data deletion.
The PowerStore File-level retention (FLR) feature allows a WORM storage device to be created by creating a PowerStore file system and then setting the file-level retention. There are two levels of file-level retention with this feature, Enterprise (FLR-E) and Compliance (FLR-C). Essentially FLR-E prevents data changes from users and storage administrators to individual files, but the storage administrator can delete the entire file system. FLR-C prevents all deletion, including deletion of the file system.
To create a PowerStore file system to be used as a WORM device, enable FLR, select Enterprise or Compliance, and then leave the default and maximum retention period set to Unlimited.
Once the file system is in place, digests for Ledger tables can then be created and stored on the PowerStore file system with File-level retention enabled.
Complete details about PowerStore and Ledger can be found in the blog post PowerStore and SQL Server Ledger – Your Data Has Never Been More Secure!. Additional information on how to configure digest storage for on-premises WORM storage in general is in the following Microsoft article: https://techcommunity.microsoft.com/t5/sql-server-blog/ledger-automatic-digest-upload-for-sql-server-without-azure/ba-p/3630992.