Inheriting ZFS Properties

All settable properties, with the exception of quotas and reservations, inherit their value from their parent, unless a quota or reservation is explicitly set on the child. If no ancestor has an explicit value set for an inherited property, the default value for the property is used. You can use the zfs inherit command to clear a property setting, thus causing the setting to be inherited from the parent.

The following example uses the zfs set command to turn on compression for the tank/home/bonwick file system. Then, zfs inherit is used to unset the compression property, thus causing the property to inherit the default setting of off. Because neither home nor tank have the compression property set locally, the default value is used. If both had compression on, the value set in the most immediate ancestor would be used (home in this example).

# zfs set compression=on tank/home/bonwick
# zfs get -r compression tank
NAME             PROPERTY      VALUE                    SOURCE
tank             compression   off                      default
tank/home        compression   off                      default
tank/home/bonwick compression   on                      local
# zfs inherit compression tank/home/bonwick
# zfs get -r compression tank
NAME             PROPERTY      VALUE                    SOURCE
tank             compression   off                      default
tank/home        compression   off                      default
tank/home/bonwick compression  off                      default

The inherit subcommand is applied recursively when the -r option is specified. In the following example, the command causes the value for the compression property to be inherited by tank/home and any descendents it might have.

# zfs inherit -r compression tank/home

Be aware that the use of the -r option clears the current property setting for all descendent datasets.

For more information about the zfs command, see zfs(1M).