adding fourth drive to existing array

Ok, the ex-wife bought a drobo and fitted it with three 1TB disks, copied the data off her existing 1.5TB drive onto the drobo and then added that 1.5TB disk in the fourth slot.

The expected behaviour was for drobo to expand onto the fourth disk giving an increase in available space. What actually happened was that the drobo dropped the first 1TB disk and rebuilt itself (taking about 20 hours) onto the three disks of 1+1+1.5

It’s finished the rebuild now. The dashboard does not see the first 1TB drive and there’s no light next to it on the physical unit. The drobo is at current fimware on a Mac.

I expect that the correct thing to do now will be to remove the 1TB disk thats not in use, wait a few moments and then put it back in, which should trigger the expansion, but could someone confirm or enlighten on this point please?

Many thanks.

You can do that or reboot your drobo.

I’d be concerned that it dropped the first 1tb disk, thats not expected behaviour

i would be suspicious about loose connections - maybe inserting your new drive it nudged something

do let us know how you get on

The unit has been rebooted with no change, I also suspect a loose connection. Thanks for the comments, I’ll see what happens when the drive is reseated and will update.

Yup, removing the drive and reseating it gave a red light for a moment and then blank, she power cycled it and the drive came up green this time, and more space was available. Woo :slight_smile:

Thanks for the tips all.

Glad its sorted

Just remember that to check your drives are firmly seated should you ever move drobo

Oddly, I just bought a Drobo S and immediately shoved five drives into it. The Drobo was on its back, so the drives dropped in vertically and seated firmly.

When I turned on the Drobo, two of the five drives didn’t show up. I had to pull and reseat them; in one case, twice.

I think the contacts in a new Drobo may get a fine film of oil deposited on them in manufacturing or something. Sometimes the only way to get a drive recognized is to pull and reseat it several times, even if it was firmly seated the first time, if it’s the first time that particular bay has had a drive in it.