Global Name Space in cDOT/ONTAP is a true UNIX/Linux based 'Pseudo File Systems'

Global Name Space in cDOT is result of a 'Pseudo File Systems' in cDOT architecture: The clustered Data ONTAP architecture has made it possible to have a true pseudofile system, which complies with the RFC 7530 NFSv4 standards.

Servers that limit NFS access to "shares" or "exported" file systems should provide a pseudo-file system into which the exported file systems can be integrated, so that clients can browse the server's namespace. The clients' view of a pseudo-file system will be limited to paths that lead to exported file systems.

NFSv4 servers avoid this namespace inconsistency by presenting all the exports within the framework of a single-server namespace.  An NFSv4 client uses LOOKUP and READDIR operations to browse seamlessly from one export to another.  Portions of the server namespace that are not exported are bridged via a "pseudo-file system" that provides a view of exported directories only.  A pseudo-file system has a unique fsid and behaves like a normal, read-only file system.