Issues with 5N- In RO mode, unsure what to do next

Hi all,

I’ve two 5Ns (and an FS gathering dust in the corner), but I’m having problems with one of them, (let’s call her Eve).

Eve and Alice (her soulmate) both run SDR on current firmware. Eve has 5x3TB WD Red, Alice has a mixed pack of left-overs. Eve was the main machine, Alice was a whimsical acquisition a while back that I have just messed around with until recently. Interestingly, Alice’s fan has always been noticeably louder than Eve’s, one of the reasons I haven’t done a lot with her.

Eve used to store files, backups and media, but more recently, as my media library has grown in size I’ve decided to reprioritise and put all my media on to Alice, leaving Eve free to do time machine backups and serve data files.

With that in mind, I had a strategy - make the quieter Drobo the media library, then clean up the fileserver / backup machine and order a new fan for her to see if she’d get quieter.

  1. Swap Eve and Alice’s disk packs around (the fan noise thing)
  2. Disk by disk swap out the WD Red’s in to Alice to increase her capacity and efficiency, whilst at the same to cleaning out the crud on Eve.
  3. Buy an nice shiny set of WD Red Pro’s for Alice, and give Eve the 3TB WD Reds back.
  4. Replace Eve’s fan.

All has been going well. Step one, fine.

Step 2, disks 1 and 2, fine. Disk 3, Eve got stuck in a reboot loop whilst repairing the disk pack.

I have now successfully put Eve in RO mode and she is reporting her status as this:

Does this mean (as I suspect) that the rebuild of the disk pack has failed because the 2TB disk is too small? When I did the calculation before commencing, I reckoned it would leave me with 11% capacity, but I admit I may have misjudged.

Any suggestions welcome.


11% would still be a “low” capacity state (an orange light)

it won’t rebuild to that state… it will only rebuild to at least 20% free

Ah… OK.

So I swap back in a 3TB+ drive and all should be fine?

I must admit I was concerned about that on the way but I had [? mis]read that 10% was the threshold limit.



So this doesn’t appear to be getting better. Eve appears to be fine in RO mode: four green and one red drive. However, I cannot connect to her via smb or SSH.

when I swap in a new drive in place of the red drive I get 5 red drives saying my disk pack in knackered.

Thoughts appreciated…