Driveletters

Windows Drive letters

There is a new dataset property called driveletter

         driveletter     YES       NO   off | on | A-Z

By default, the value of driveletter is "-", which means

 If this is pool's root dataset:  driveletter = on
 If other dataset: driveletter = off

 $ ./zfs.exe mount
 tank                            E:\
 tank/lower                      tank/lower

This effectively means the pool itself will get the first available driveletter, for example, E:, and a lower dataset will be mounted inside the pool. E:/lower.

If the root's dataset is set to driveletter = off it will mount the pool inside your default OS volume.

 zfs set driveletter=off tank
 zpool export tank
 zpool import tank
 zfs mount
 tank             C:\tank

If a lower dataset is set to driveletter = on it will also get a driveletter. The pool is assumed to be on here.

 zfs set driveletter=on tank/lower
 zpool export tank
 zpool import tank
 zfs mount
 tank             E:\
 tank/lower       F:\

You can also explicitly set a driveletter, by using driveletter=A-Z

 zfs set driveletter=Z tank
 zpool export tank
 zpool import tank
 zfs mount
 tank             Z:\