In this video I show how to install ZFS file system on Ubuntu and configure a zpool with only one disk. Then we take that existing ZFS pool and add an additional disk to the pool to make it a mirror for some redundancy. Install ZFS # apt install zfsutils Create the ZFS pool # zpool create datastore sdb Show the pool status and mount point: # zfs list # zpool status # zpool status datastore # mount -l Check volume sizes # df -h Add disk to existing pool and create mirror from it: # zpool attach datastore sdb sdc Show the pool status and mount point # zfs list # zpool status