Home > Data Protection > PowerProtect DD Series Appliances > PowerProtect DD Data Invulnerability Architecture: Enhancing Data Integrity and Recoverability > Self-describing data format to ensure metadata recoverability
Metadata structures, such as indexes that accelerate access, are rebuildable from the data on disk. All data is stored with metadata that describes it. If a metadata structure is somehow corrupted, two levels of recoverability exist. First, a snapshot is taken of the file system metadata every several hours; recoverability can rely on this point-in-time copy. Second, the data can be scanned on disk and the metadata structure can be rebuilt. These capabilities enable recoverability even if a corruption of the file system or its metadata occurs.