Can I take a new WD Red Pro 18TB hard drive

Can I take a new WD Red Pro 18TB hard drive in my drobo 5t?

You will need to ask Drobo Support.

As @TwinTiger said, it’s contact support to be certain, the thing is 16 TiB is one of “those” numbers where things break unless they’ve been written recently enough to allow for passing it. So 16TB is likely to function even if that wasn’t officially covered, but going beyond runs a risk things break owing to the addressing of the number of blocks requiring too many bits of address space.

Hardware limitations might or might not also come into play.

Thank you. I think, it is better to wait for a new firmware version.

The largest drive size tested by Drobo is 14TB, as per this article: Maximum Volume Size and Largest Size Drive

However, the same article shows that the maximum volume size is 64TB. The capacity calculator (Capacity Calculator - Drobo) shows that a volume will reach a size ~50TB if the device is populated entirely with 14TB drives.

So, by necessity, in order to reach the maximum 64TB volume size, drives larger than 14TB will need to be supported. Unless my logic is off. :slight_smile:


I had a similar question some time back, and shared the information Drobo Support provided at the time, which may assist you:

Thanks for the details! That answers the question for 16TB drives. I suppose I should open a support ticket to know if 18TB drives would cause an issue.

Did you get a reply about 18TB drives? Thanks, ==mwh

I never got around to opening the ticket with support las time. I just did today. I’ll let you know what they respond. :slight_smile:

@mwhelm I got a response from Drobo support:

"We have not tested drives that large, they will very likely work.
Just keep in mind the models we do not recommend - Can I really use any hard drive I want in Drobo?
​Make sure any drive you buy for a Drobo does not use SMR technology for storage. Any drive using that is not compatible.

You are also still limited to the 64TB volume size.
So, if you were to fill a unit with 18TB drives you would be over that volume limits and that extra space would be unusable anyway.
5 x 16TB drives in a 5N2 would put you at exactly 64TB usable space (4x16 because 1 drive is the redundancy drive)"

I hope that helps!

Thanks. I guess I have to risk it and try one. I think I can use it elsewhere if it doesn’t work in the Drobo.
I’m using dual drive failure redundancy (i have had 2 drives fail simultaneously) & I think for that drives of about 24TB would be needed to max out 64TB. 18TB I estimate would be about 49 TB space. If so the drive capacity ceiling is well above what is available right now.

I can say that my old DroboFS was using 12TB drives in it without a problem. The maximum tested drive was 4TB. I’m pretty sure the 18TB drive will work just fine in my 5N2. And I’m pretty sure the 5Dt will work on the same principles as the 5N2, since they have the same max volume size, etc.

i have now over 64 tb and works