This is an old revision of the document!
The built in NFS server allows file sharing capabilities with NFS clients (mainly Un*x like systems). It's essentially the equivalent of samba in a Linux environment.
Enable NFS Server - Runs the NFS server process.
Enable legacy (NFS V2) support - NFS currenly has 3 version - NFS 2/3/4. FreshTomato defaults to v3, but with this option it can be enabled to “speak” v2 also.
Directory - This specifies the filesystem location to be shared.
IP Address/Subnet - Limits connectivity to the IP address/subnet you enter in this field.
Access - Defines the share permissions (how the share can be accessed)
Sync/Async - Sync means that data are immediately flushed to disk, whereas Async (rarely used) takes a asynchronous approach.
Subtree_check - Helps when one folder is exported but one or more of the subfolders is not.
Other_options - Here you can specify advanced options. Please refer to the official NFS documentation for additional details.