I have my Drobo S set-up with [4x 4TB and 1x 6TB] drives without DualDisk Redundancy turned OFF.
I only have 3.46TB of data on the Drobo S, and I need the 6TB drive in a different array. So, I turned the unit off and removed the 6TB drive… and replaced it with a freshly wiped 500GB drive I had laying around.
The device refuses to implement the 500GB, and is giving me a Red Light and telling me to insert more larger drives (see screenshot at http://i.imgur.com/KA0F2Mi.png)
I tried removing the 500GB, to see if the unit would just reallocate to the 4 drives… but it will not. It demands I insert a fifth drive.
How can I get the Drobo S to accept the 500GB drive and rebuild across the [4x 4TB + 1x 500GB] setup without data loss??
[[UPDATE NOTE: As I’m reading through other people’s issues in the forums, I had earlier in the day deleted almost 7TB of data from the Drobo to get it down to a size so I could remove the 6TB drive. Perhaps the device was still silently rebuilding itself after the data purge?
I have since replaced the 6TB in the array and it is Green/Yellow blinking and rebuilding itself over the next 84 hours…]]
Yes, I removed the 6TB and inserted the 500GB while the unit was off.
I tried reseating it with the power on, and got no joy. I reinstalled the 6TB with power on… and now it still has 90+ hours to rebuild. I’ll try again in a few days.
To be clear, you meant that hot-installing would erase the 500GB drive, correct? (Which is fine, I slicked it anyway).
Drobo does indeed do a form of trash collection, so if you have only just deleted a large amount of data, it may well take a day or two to actually free up those blocks.
I’d leave the 500gb drive in place, complete with red light, for at least 72 hours … drobo may suddenly start rebuilding all by itself once its relasies it does have enough space.
alternatively after waiting 72 hours, sometimes restarting drobo is all that is needed to kick start a rebuild.
Well, after a 4 day rebuild and reshuffle… The machine was back to having 5 green lights for the 4x4TB/1x6TB arrangement.
I left the power on and “hot-swapped” in the 500GB drive for the 6TB… and I have the same red-light scenario as before with the error: “Drobo cannot protect your data against hard drive failures until you provide at least 2 hard drives for single disk redundancy or 3 hard drives for dual disk. Replace the hard drive indicated by the red light with a larger capacity drive to enable Drobo to protect your data against hard drive failure.”
I’ll give it a few hours, maybe it will start a rebuild and clear itself…
I do not believe it is a bad drive, I’ve connected it to my laptop and done some file transfers and re-slicking…
After a few days, the Drobo S never rebuilt itself. I did see it try once, all the drives were flashing yellow/green for about 10 minutes… then it went back to highlighting the drive as Red and giving me the error “Drobo cannot protect your data against hard drive failures until you provide at least 2 hard drives for single disk redundancy or 3 hard drives for dual disk. Replace the hard drive indicated by the red light with a larger capacity drive to enable Drobo to protect your data against hard drive failure.”
I emptied it of data, and reformatted the Drobo S but that did not fix the issue. So then I used the Drobo Dashboard to initiate a full reset on the device… and now it is working perfectly and recognizes all five drives (4x4TB & 1x500GB). So, I guess the answer is sometimes you just need to do a full factory reset if it stops recognizing a drive in a certain bay.
