The Data ONTAP operating system implements a single proprietary file-system called WAFL.
When used for file storage, Data ONTAP is capable of acting as both a NFS server and/or a CIFS server, contingent on licensing and configuration. It is therefore capable of serving files to both Unix-like clients and to Microsoft Windows clients from the same file systems.
This makes it possible for Unix and Windows to share files by the use of three security styles: mixed, ntfs, and unix. Data ONTAP supports user, group, and tree-based quotas (referred to as q-trees) and allows for data segregation and management within volumes.
Qtrees with the UNIX security style will preserve the standard Unix permission-bits, the NTFS security style will preserve NT ACLs found in the Windows environment, and the mixed security allows the use of both interchangeably (with minor loss of fidelity).

Since 2002, all NetApp FAS systems can also work as SAN storage over “block-based” protocols such as FC, iSCSI and FCoE (since 2007)
Although FreeBSD is familiar to Data ONTAP GX users, it is a departure from Data ONTAP 7G.
The use of FreeBSD as the operating system for Data ONTAP 8.0 allows for some significant benefits. Besides the fact that Data ONTAP will continuously benefit from the third-party work taking place within the FreeBSD community, the clean separation of the operating system from the file system allows for focused innovation within the file system itself.


Above figure shows the software stack that makes up Data ONTAP 8.0 7-mode.
Although 7-mode runs in FreeBSD with a new data component called the D-blade and a new management component called the M-host, it acts very much like Data ONTAP 7G. The NAS and SAN protocols are handled by the D-blade.

The D-blade is the data blade. It manages the storage attached to a node, and provides the WAFL (Write Anywhere File Layout) file system to map data containers and their associated metadata and attributes to disk blocks. In 7-mode, the D-blade services NAS and SAN protocol requests. It also provides the 7G compatible node user interface.