Also it worth noting, that usage of JBOD isn't recommended for older Cassandra versions, as there are known issues with data imbalance on JBOD.
iirc JBOD data imbalance was fixed in some 3.x version (3.2?)
For older versions creation one large filesystem on top md or lvm device seems to be a better choice.
From: Eunsu Kim <eunsu.bill23@xxxxxxxxx>
Sent: Tuesday, June 12, 2018 9:06:07 AM
Subject: Re: What will happen after adding another data disk
In my experience, adding a new disk and restarting the Cassandra process slowly distributes the disk usage evenly, so that existing disks have less disk usage