15.9 TB Free?

Can someone tell me why my Drobo FS is reporting 15.9 TB free? I currently have two 1.5 TB and one 2.0 TB drives installed. The drobo dashboard is correct, but the free space reporting by the operating system (windows 7) show 15.9 TB free.

This is perfectly normal. Drobo will report whatever the volume size you’ve formatted it with to the operating system, for consistency’s sake.

Hmm. Could you explain further? I did not explicitly format the drobo. I just started with two 1.5TBs, then added the 2.0TB, and this morning I added another 1.5TB… finally I will add the last 2.0TB tonight. The Drobo dashboard is reporting everything just fine, I am just curious as to why Windows 7 is reporting all of the shares as having 15.9 TB free. Its a pretty strange (and large) number. At one point in the begining, I believe Windows was reporting the available space correctly. Perhaps the change occured after I went beyond 2 TBs? Can anyone offer any insight?

Drobo is based off of ‘Thin Provisioning’ so it reports 16TBs to the OS so you can increase the capacity of your Drobo on the fly without having to make major changes to the OS. If you research the forums, you’ll find out more about this.

Thanks much! I will research.

The Drobo FS automatically formats to a 16TB EXT3 volume.

Perhaps I should go researching through the forums more myself, but I recently purchased a FS and was wondering this very same thing.

So, say you have a 6TB share but the OS mounting the share shows 16TB free. What happens when you attempt to copy more to the Drobo share beyond the 6TB? Just a “No space left on device” ? It’d be nice if the OS mounting the shares could reflect the real amount of data w/o having to bring up the Dashboard (or checking the pretty lights).

If you have email set up, Drobo FS will warn you when you get close to filling up the NAS. From what I can tell, other than that, you will have to rely on the blue led status lights on the DroboFS or status information from DroboDashboard. It looks like if you attempt to write pass the physical limit of the FS, you will corrupt files and potentially destablize the FS.

Wow!! That sounds like a rather poor design decision. Does it have that issue nomatter which client OS you mount the shares with? I’d assume it would…

I hope the Drobo folks can do something about that… c.c

I myself thought it was kind of sexy seeing a 16tb volume show up on my desktop. I know the real capacity story from Drobo Dashboard or the blue status lights on the front of the device.

I asked the same question and found this which answered my question: