Integrity streams is an optional feature in ReFS that validates and maintains data integrity using checksums. While ReFS always uses checksums for metadata, ReFS doesn't, by default, generate or validate checksums for file data. Integrity streams is an optional feature that allows users to utilize checksums for file data. When integrity streams are enabled, ReFS can clearly determine if data is valid or corrupt. Additionally, ReFS and Storage Spaces can jointly correct corrupt metadata and data automatically.
Integrity streams can be enabled for individual files, directories, or the entire volume, and integrity stream settings can be toggled at any time. Additionally, integrity stream settings for files and directories are inherited from their parent directories.