Drobo FS only recognizing 10TB of 14TB storage

I have a Drobo FS that originally had 5 2TB drives (~10TB and about 7TB usable). Once of the drives went bad so I thought I would slowly upgrade the space on the drobo and replaced the 2TB drive with a 6TB drive so that the configuration is now


It is showing that I have 1TB left of storage and 7.24TB Used (approximately 8TB total) however when I look at the usage tab in the drobo dashboard, it shows.

Drives: 2TB + 6TB + 2TB + 2TB + 2TB + 14TB (12.73TB Actual)

However, I am seeing low space issue on the first drive (2TB) and the warning states:

“Yellow Warning: Drobo is running low on protected space. Replace the hard drive indicated by the yellow light.”

The one that is yellow is the first drive in the series and the drive in bold above (a 2TB drive)

Any ideas why it can’t use the extra storage on the 6TB drive to compensate?


Drobos in single drive redundancy use the largest drive as the redundancy, and you get the sum of all the rest as your total storage. Replacing one drive in your original setup with a bigger one will do nothing to your available space. There’s no way around this with the drives you have. If you replace another 2TB with a bigger drive then the additional storage will add to your available total. The Drobo always seems to point to the first drive when it thinks you’re low on space, but in reality replacing ANY of your 2TB drives with a larger one will be just fine. I always put bigger drives in in pairs, you lose one of them but all of the second one adds to your available total.

So I have a similar situation with my Drobo-FS. Got the yellow warning. I had 5 x 3TB drives (total space 10.87 TB). So I replaced the top one with a 4TB. After it was done copying the data to the new drive the 2nd drive in my bay got the yellow warning and the amount of available space did not change. So changing the 2nd one should give me more space and get rid of the yellow warning??

hi marc, yes i think once you upgrade your 2nd drive to a larger size, you will end up with more usable space)

btw this thread is quite cool because the first poster was about The Beef, and now your nickname is a chef :slight_smile:
(i guess spiney could be a type of fish too) :slight_smile:

I’ve been told the Drobo-FS is supposed to recognize 4TB drives for a moment I thought maybe it didn’t . Hopefully adding another one will fix it.

PS All that food talk made me hungry!

hehe, ok sure please let us know how things go :slight_smile: