How to set up now to "futureproof" for drive size increase?

Ok, so I apologize for my general noobness and the long post.

I’m finally starting to set up a TrueNAS Scale NAS.

Hardware is a basic MB (i3-n305), 16G RAM, a 250G SSD OS drive, SATA 3 and 8x12 TB (Seagate Exos x14) storage drives in a 2U chassis.

Software is going to be TrueNAS Scale. I was planning on setting up one pool in a RaidZ2 configuration.

I expect to keep running this NAS for the long term (several years, certainly, probably longer) without upgrading the core HW. That said, I expect that larger size drives will drop in cost as time moves on. I understand the whole “the array must use the size of the smallest capacity disk” concept, but here’s my question.

If I were to buy a couple of larger drives a month, rather than all 8 at once, is there something I should do in my setup now to make it easier to replace one drive at a time with larger capacity units?

From the documentation, it sounds like if I were to replace fhe 12TB drives one at a time with (say) 24TB units, the system would just recognize them as 12TB drives until the moment I replace the last one, then it would rebuild automatically, expanding the array to 24T a drive based off the now larger size of all of the disks.

Is there a way to use that extra space somehow before the 8th drive goes in? (It honestly looks like the answer to this is “no”, and that’s fine.)

More importantly, is there something I should do to setup my system now to make it easier for me to upgrade the drives later? (This, I really don’t know.)

TIA!

No. The only caveat is that the larger drives will not yield any additional capacity until all drives in a vdev are replaced. (This assumes the SCALE “partitioning” bug has been fixed, which I think it has.)


Not “rebuild”. It just expands the pool’s total capacity. This should happen automatically, but some users had to manual invoke this by pressing the “Expand” option in the GUI.


Not really. It will be partitioned to yield a 24-TiB partition, but only 12 TiB will be used because of the other member devices’ space limitation. (Querying the pool will treat it as a 12-TiB member device in the vdev. After you properly expand the pool by replacing all drives, it becomes a 24-TiB member device, as do the others.)


"Yes."

Only with the command-line. Only if you hate your data. Only if you are a masochist. More importantly, why would you? The data will only be erased when the extra space is needed for the pool expansion…