ReadyNAS Ultra 6 Plus.... 18TB -> 24TB

frusnet wrote:
Now the question remains: Will I be able to make this transition simply by "pulling old 3TB/inserting new 4TB/wait-for-syncing" drives one-by-one?

As we've already said, it depends on the answers to other questions mdgm asked.

With the ultra-6 you can expand a volume by 8 TB over its lifetime. That is the volume size, not the raw disk capacity.

So your 6x3TB array is giving you 12 TB of capacity now (~11 TiB). You will be wanting to expand it to 16 TB (14.5 TB)

There are two expansion limits:

(a) you can't expand beyond 16 TiB. You are ok on that one, as you aren't trying to do that.
(b) you can't grow a volume more than 8 TB over its lifetime. That starts from the initial install or the most recent factory reset.

So we need to know the starting point in order to tell if the hot swap approach will work. If you started with 6x3TB it will. If you started with 4x2TB it wouldn't.

Also, you will need to install 4 of the larger drives in order to see any expansion.