Windows driveletter

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 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:\