Add a drive to a ZFS pool with a single drive

[MentalNomad]

Resolved.

 

[Dunuin]

You need to use the zpool command to manipulate your ZFS pool.
For a raid1: https://openzfs.github.io/openzfs-docs/man/8/zpool-attach.8.html
For a raid0: https://openzfs.github.io/openzfs-docs/man/8/zpool-add.8.html