Drobo Gen 2 - worth the pain to reformat?

I have a Gen 2 drobo, in which I’m shortly upgrading one of the drives from 1 TB to a 4 TB WD Red expected delivery early next week, installation after I’ve run badblocks over it from a linux live cd, to check it’s 100%

The current config is:

8 TB partition (LUN) formatted NTFS
installed drives-
1 TB
4 TB
1.5 TB
1.5 TB

I’m in two minds if it’s worth copying my data, mostly backup sets for the entire family, off the drobo to the new drive (should just fit), then setting it up as a 16 TB LUN, then copying back prior to installing the new drive, or if I should leave things alone and just replace the drive?

Since Gen 2s only officially support 4 TB drives is 16 TB a good plan anyway? or would something around 11 TB make more sense since this is approximately the capacity I’d see with 4 x 4 TB drives in it?

Also, I see others have fitted 6TB drives in these units, even though not officially supported, does this cause issues (apart from long rebuild times)?

If these are OK, then 16 TB would be about right if /when I’ve ever populated it with those, Gen 2 being EOL I’m not seeing any chance of a firmware update to give official support for drives over 4 TB.

I can probably live with the existing LUN size without much pain, then again, if I get some money, and I’d done the format now, while the data will still fit elsewhere temporarily, then I could migrate the entire pack to a newer chassis (gen 3) at some time in the future and have a shorter data transfer time now, rather than doing the job then and it taking longer.

Decisions decisions :s

I’m so old that I remember when we partitioned hard drives in case something went wrong with one filesystem, the other would survive.
If you require a single volume, and if you are comfortable putting that much data on a Gen2 with single parity and rebuild time measured in weeks, then reformatting sounds like your best option.

I remember that too, I’m comfortable putting this data on a Gen2 with single parity, it’s almost exclusively 2nd backup sets of machines which image themselves to a spare internal drive, ie. easily recreated data, which is stored in the original location and another. I learned never to rely on backups in a single place the hard way and I certainly trust single parity and long rebuild times more than storing them in a slew of standard USB external drives, with no parity, and no possibility of rebuilds, or an old p4 Linux box running samba, software raid, and lvm, which are my other options.

Well I went ahead, and it went without hitch, though it was a slow process.

Hello! I really liked your story. Thank you!