In reference to Upgrading Hardware
In the event that you are upgrading your hardware, note that by design, Aerospike distributes the data evenly across all nodes in the cluster, so we assume that all of the servers have equivalent capacity. For best performance, we recommend that all nodes in a cluster have equal storage. If you add a new node with a larger SSD, the full capacity of that SSD will not be used effectively unless the other nodes are upgraded to have the same capacity.
could some one please explain why is it that the server will not be able to use the larger SSD to its full capacity? and what does it mean by not utilizung it to its full capacity