Scaling this setup is relatively straightforward. As previously mentioned, we can either scale vertically, by adding more disks to each of the nodes, or scale horizontally, by adding more nodes to the cluster.
Scaling vertically is considerably simpler than horizontally as it requires fewer resources. For example, a single disk can be added to the ZFS pool on each of the nodes—effectively increasing the available space by 256 GB if three 128 GB disks are added.
Adding disks to the ZFS pool can be done with the following command:
zpool add brick1 /dev/disk/by-id/<disk-id>
From the previous command, brick1 is the name of the pool and disk-id is the UUID of the recently added disk or disks.
Scaling horizontally requires the exact setup to be mirrored on a new node and then added to the cluster. This requires a new set of disks. The advantage is that the available...
