What I am looking to do is, one by one, replace the drives in my current raid array (in a 1680i). After the drives are replaced by their larger counterparts, I want to do an online expand of the array. Can this be done?
I have an Areca ARC-1231 controller, apparently they use the same driver.
These have a separate notion of Raid Set (collection of disks sharing a common size) and Raid Volumes (which span across part of all the disks of the Raid Set and have a defined size and raid level.)
I have not attempted it yet, but querying the Raid Set shows a Min Member Disk Size and no way to set a size by hand, so I guess once you'd have replaced all the disks in the raid set, they will be free capacity on the raid set, at which point you should be able to grow the volume inside the raidset (with the CLI the command is something like