ZFS Sharing Inheritance in Older Pools

In older pools, only the sharenfs and sharesmb properties are inherited by descendent file systems. Other sharing characteristics are stored in the .zfs/shares file for each share and are not inherited.

A special rule is that whenever a new file system is created that inherits sharenfs or sharesmb from its parent, a default share is created for that file system from the sharenfs or sharesmb value. Note that when sharenfs is simply on, the default share that is created in a descendent file system has only the default NFS characteristics. For example:

$ zpool get version tank
NAME  PROPERTY  VALUE  SOURCE
tank  version   33     default
$ zfs create -o sharenfs=on tank/home
$ zfs create tank/home/userA
$ grep tank/home /etc/dfs/sharetab
/tank/home      tank_home       nfs     sec=sys,rw
/tank/home/userA        tank_home_userA nfs     sec=sys,r