Abstract
There are a few authorization domains used widely today: POSIX mode bits and CIFS/NFSv4 Access Control Lists. Creating a file system which intelligently maps between different sets of file permissions is tricky. I will explain how we accomplish this in Isilon’s OneFS operating system. By mapping ACLs from one authorization domain to the other, our clustered file server provides one unified permissions model for CIFS, NFSv3 and NFSv4 clients.