Drobo S - Why *Not* seeing Blinking Orange and Green ?

Can someone shed some light on this:

I recently purchased a Drobo S and I copied my first big set of files to it. I copied 37GB of files to the “Drobo S”, but I never saw the bay lights flash between orange and and green. Bay lights stayed green during the 46 minute copy operation, whenever I periodically came back to my desk to view the Drobo S.


… So, did my data get protected and written to the other drives (I have 3 drives) in the Drobo S ???
… Why did I not see flashing orange and green lights ? Is something not working right with my Drobo S ?

… Is my data being protected ? Is there a way to double check ?

BTW … I checked Drobo Dashbaord and it is says data protected. But, why didn’t I see blinking orange and green lights ?

You should only see orange-green blinking when you remove a drive or a drive dies.

Once Drobo is set up, it remains in a protected state on-the-fly.


So, if you can just confirm that I have the below correct then …

  1. It flashes orange and green, only when “re-building” due to removing a drive. … I assume then also adding a drive would be “re-building” and therefore also flash orange and green ???

  2. So, I assume then as soon as files are copied to/written to the Drobo they will instantly be replicated across the multiple drives in the drobo and just the activity light should blink green and the drive bay lights should stay green.

Hey Joseph,

  1. It flashes orange(amber)-green when data protection is in process, in other words, when redundancy data is being rebuilt. In the case of Single Disk Redundancy (SDR), your data is not protected during this time. If you have Dual Disk Redundancy (DDR) then your data is still protected, unless two drives have been removed or failed.
    When simply adding a drive to an empty bay, data is still protected and Drobo does the background shuffling to optimize the storage usage in the background.
    Since the existing data is still protected during this process and any additional data added to the Drobo is already protected “on the fly” you don’t get the orange-green blinking.

  2. Correct.

Docchris is one of the local experts on the magical Drobo processes, so he can elaborate more if you need.


…Very informative !!! Thanks fo the detailed description of the drobo process !

… But another question, just to clarify one point:

==> "when redundancy data is being rebuilt. In the case of Single Disk Redundancy (SDR), your data is not protected during this time. <===

Do you mean “data is not protected during this time”, from another drive failure or do you mean from a power outage during the “re-building” process ?

You are not protected from drive failure. If power goes out, it should continue the rebuild when power is restored. That said, it is still a good idea to put your Drobo and attached computer on a UPS so you don’t get filesystem corruption due to power outages.

Just one last clarification,
… So, if your unlucky in the sense that the replacement drive that you just inserted (to replace a failed drive) fails during its re-build process, under sdr your data is lost. However, if you had ddr enabled your data would not be lost , you would just insert a new replacement drive to replace the replacement drive that failed during the re-build process ?

actually generally no…

if you have 4 drives… and you pull one (the 4th say)and replace it with a new drive… if that new drive dies… then in theory drobo still has all your data on the original 3 (it was just rebuilding onto the 4th) so once it asks you replace your 4th drive (NOT BEFORE) you can just pull your new-but-dead drive adn replace it with a differnet 4th drive. and it will just recommence rebuilding for a second time.

however if one of your remaining 3 drive dies during a rebuild process - then you have a disaster!

their support pages / knowledge base is actually pretty good, here’s the rticle about what you just asked:


and to clarify an answer to one of your previous questions. if you were to have 3 drives & everything was protected (solid green) and ADD a 4th… then there would be no flashing yellow/green lights.

it only flashes when its protecting your data. your data was already protected on 3 disks and since you have only added a 4th, that storage is added to the pool and at no point would your data be at risk… it would remain protected even though drobo may be silently re-arranging data to put some onto the 4th disk - you would never be “at risk” so it would never flash. since the lights are solid green you could still remove any drive safely during drobo’s internal housekeeping (which is why it doesn’t tell you not to - by flashing)

hope that all helps


Thanks for explanation ! Concept is clear to me now.

glad to be of help :slight_smile: