Image a hypothetical scenario having two 512 GB drives and want to use a Proxmox ZFS VM replication onto a second server with one 1 TB drive. Solution is quite simple. By using fdisk, create two primary partitions on the bigger drive and then go to Disks.ZFS.CreateZFS and you will be able to select a partition for the particular pool. One downside of such a setup is that ZFS liks to have whole drive for it’s own, please keep in mind that the performance may vary.