“ReFs” or Resilient File System is a new file system written from scratch for Windows 8. ReFs is compatible with NTFS and is supposed to reduce complexity while being able to automatically detect corruption on RAIDed disks.
“…Together, Storage Spaces and ReFS have been architected with headroom to innovate further, and we expect that we will see ReFS as the next massively deployed File System…” said Microsoft’s storage and file-system development manager, Surendra Verma.
“Storage Space” stripes data on more than one physical disk to protect against data loss caused by disk failure. Storage Space and ReFs work together recover data when failures or corruption is found.
ReFs is currently limited to Windows 8 Server beta testers but Microsoft expects it will be available on Windows 8 at some point in the future, which likely means it will NOT be at launch in the fall of 2012.
Existing NTFS commands (or API’s) will function seamlessly as will Access Control Lists, BitLocker, Junction Points, Mount Points and Snapshots. However, encryption, short names and quotas are NOT supported. Further, you can not boot from a ReFs disk it (today) can not be read be previous versions of Windows, including Win 7.
ReFs is the offspring of Vista’s illfated WinFS. It was originally called Monolithic NTFS (MNTFS) and then became codename Protogon.