Strange disk replacement behavior

my Drobo was operating with 1TB/1TB/1TB/500GB for months now and it’s filled with 1.6TB data.
Today I wanted to replace the 500GB drive with another 1TB drive.
I pulled the 500GB drive and its LED turned to RED. Drobo Dashboard said, Drobo can no longer protect my Data from any drive failure (red box) and additionally told me, I’m almost out of protected space (yellow box).
The other three LEDs stayed green, no flashing green/yellow!

Any explanation on that? Maybe, because I only use 1.6TB, the remaining three 1TB drives already had a consistent protected raid, so no re-layout was necessary? But then, why did the Dashboard tell me my Data is no longer protected (without flashing LEDs?).

After that, I pushed the new 1TB into the fourth slot. Drobo immediately started a re-layout and is doing this for hours now (Dashboard says, it will take another 32 hours?!?).

If Drobo was in a protected state with the three 1TB drives, why the hell is it doing a 35h re-layout with the new drive inserted?
And if it wasn’t, why didn’t the LEDs flash green/yellow when I pulled the drive?

Is the unit faulty?

Drobo Gen 2, FW 1.3.5
Dashboard 1.6.8 on Windows Server 2003 (which sucks btw, “DDService” fails and has to be restarted about twice a day!)

It would only have flashed green yellow with your three remaining drives if it was rebuilding onto them to get back to a safe state, since it could not (because you would not have had enough free space) it was sitting there waiting for you to insert a 4th drive to rebuild onto.

When yo did insert a 4th drive it began rebuilding onto them and yor rebuild time sounds a little long (although y o don’t say what model you have so it’s hard to tell), but it will increase if you are using the unit.

Essentially everything is working exactly as designed/expected.

I don’t agree… Green lights say “save to remove”. If drobo didn’t have enough space to rebuild a protected state, it should still have indicated that it’s in an unprotected state by flashing the lights.

However, three 1TB drives give me 1.8 TB ob protected storage. Since I used only 1.6TB Drobo should have been able to rebuild to a save state. Maybe Drobo was smart enough and didn’t use the smallest drive and already had a protected state which explains why the lights stayed green. But if that was the case, why did it tell me, my storage is not protected and started a intense rebuild after adding the new drive?

1.8 tb is NOT enough space to rebuild - that would have left you what drobo would term “critically low on space” so it didnt rebuild and instead asked you to insert a drive![hr]
flashing light do NOT indicate an unprotected state - flashing lights indicate a rebuild is in progress (which 99% of the time is ALSO an unprotected state) - since your drobo was NOT rebuilding - it didnt flash!

Well, I don’t know if 1.8TB is enough space to rebuild 1.6TB of Data. If it’s not, fine.
However: Three green LEDs tell me that my “Drobo is healthy” and the Drives are safe to remove. (This is what’s stated in the manual!)
But Drobo Dashboard (and you) tells me, that my Drobo has not been in a protected state.

This clearly is a fault!

ALL Green LEDs tell you its healthy - you had a red one too.

plus dashboard TOLD you that you were not protected


asked you to insert a new drive.

that seems exceptionally clear to me.[hr]
exactly what colour combination do you think would be good to indicate “i don’t have enough space to rebuild but i will do if you add another disk” for your existing disk pack? there are only a finite number of things they can do with the LEDs

flashing red is a failed drive

Solid red (which you got - is please urgently add a drive here)

green/yellow is rebuilding (which yours was not doing - so it couldn’t use this)

What the Dasboard tells me is not important. I use Drobo connected to a Server an usually don’t see the Dashboard at all. Drobo is designed to work without the Dasboard, so the LEDs should tell me what do do.

According to the LED description, thee green LEDs, a red LED next do the empty slot and a 9/10 capacity LEDs tell me, that my Drobo is running out of Space an I should add a drive into the empty slot.
It is NOT telling me not to remove any other drive (which would be flashing green/yellow) or that my data is not protected anymore.

(FYI, flashing green/yellow does not say “rebuilding data”, it says “don’t remove drive”).

I’m fine with my Drobo not rebuilding if it can’t, but it should tell me that my data is not protected (with the LEDs!)

as i asked HOW should it tell you with the LEDs? its designed for simplicity

i dont think its asking too much that when you make configuration changes you use the dashboard

if drobo is designed to work without dashboard - i would be fascinated to know how you set up your drobo since you need dashboard to configure the volumes…

and if its designed to work without dashboard - why do they even bother supplying it (dashboard)?

short version - you are whining about nothing, it performed EXACTLY as designed AND it gave you perfectly clear text instructions on what to do.

you are just boo-hooing that they didnt come up with some ridiculously contrived sequence of led’ flashes, which is frankly pointless and i’ve totally lost interest in your imagined problem.

and FYI - even if you DID remove another drive - it would have just asked you to re-insert it.[hr]
I’m just going to subscribe from this thread.

[quote=“Docchris, post:8, topic:1464”]
as i asked HOW should it tell you with the LEDs? its designed for simplicity[/quote]

Flashing green/yellow on the remaining three drives. As I told you, flashing green/yellow says “don’t remove drive”, it’s NOT saying “rebuilding data”. Look at you’re Drobos front plate.

Drobo is designed for simplicity, so I don’t understand why you think Drobo should only have flashed the lights if it was rebuilding. Users don’t care if Drobo is rebuilding or not! The only thing they should care about is if it’s save to remove the drive or not!

[quote=“Docchris, post:8, topic:1464”]
if drobo is designed to work without dashboard - i would be fascinated to know how you set up your drobo since you need dashboard to configure the volumes…[/quote]

Have a look at the manual. You can just plug it in and use your operating system tools to format drobo. You cannot setup more than one volume without the Dashboard, thats right, but you can use Drobo with one volume (which I do).

For >1 Volume support. For Firmware upgrades. For easy monitoring if you have the oppertunity to use the computer which Drobo is connected to…

However, DRI does not really do a good job with the Dashboard. They needed way to long to provide a Windows Service Application instead of the old Desktop Application. They even had Drobo Pro which was designed for Server use and had no Windows Service!
Now they have it, but it’s really buggy. Mine fails about twice a day on Windows Server 2003 and has to be restarted by Windows. Also the Dashboard often does not recognize changes on Drobos state without restarting the Dashboard.
When I pulled the drive, Drobo Dasboard still showed all four drives green. I had to restart it to see the change. And I had to again, when it started rebuilding.
Also my Dashboard fails to send me E-Mails (except the Test-Mails, they work :wink: )


I like to know when my Drobo is rebuilding. It tells me if something is potentially suspicious (like it’s rebuilding because a drive went offline, then came back online), or if I should expect reduced performance because it’s rebuildling.

I’ve had quite the opposite experience from you with Drobo Dashboard. I’ve never had it crash - except for one time when I had it run by two logins simultaneously on the same server. It didn’t like that.

Of course you want to know when it’s rebuilding, thats fine.

I only said that the LEDs should do what they are designed to do! And since flashing “green/yellow” means “don’t remove drive” the LEDs should not only flash while rebuilding, they should in any condition when it’s not save to remove the drive![hr]
Okay, I just had a look at my diagnostic log:

Sat Jun 05 09:57:53 2010: DPM::hotPlug: SlotNumber = 3, op = REMOVE
Sat Jun 05 09:57:53 2010: DPM::hotplug: LD #2 matches disk in slot 3 WWN=>S13TJ9CQA03793 SAMSUNGHD502IJ 1AA01113
Sat Jun 05 09:57:54 2010: DPM::updateDis: writing 0x1b77e9bf1b77ee78/27 to LDs #0 1 3 
Sat Jun 05 09:57:54 2010: SM: remove physical disk 3 (logical disk 2)
Sat Jun 05 09:57:54 2010: Capacity: Free=130.12GiB(7.11%), Used=1.66TiB(92.89%), Total=1.78TiB, Unprotected=0B.
Sat Jun 05 09:57:54 2010: LM: rebuild initiated as logical disk 2 removed
Sat Jun 05 09:58:21 2010: DPM::hotPlug: SlotNumber = 3, op = ADD
Sat Jun 05 09:58:22 2010: LM: rebuild completed in 28Secs

According to this, Drobo did a rebuild after removing the fourth drive. So why didn’t the Lights flash?!

They rebuild you are seeing is the drobo removing the logical disk from the disk pack. It’s not a full rebuild of your data.

So actually no data was stored on the fourth drive that I removed?

Data is on all 3 drives then broken up into metafiles on each drive. If you remove a drive when all of them are green. You are still able to access ALL your data.

Yes, but that didn’t answer my question.

I was concerned because removing one of my four drives did not trigger a rebuild. I’d expected the LEDs of the remaining drives to flash for some time, but they didn’t.

So again: Is it possible that all (redundant!) data had been stored on the first three drives and the fourth had not been used by Drobo at all? Because if it had, removing it must have caused a rebuild.

It did not trigger a rebuild that YOU were expecting because you had no space available on those drive for the full rebuild. Dashboard immediately showed a solid red light on that empty bay and dashboard said, you are critically low on space and you are not protected, add a hard drive.

Once you added that hard drive, you had enough space to trigger the big rebuild.

So you confirm that (after removing fourth drive) my data was not protected against an additional failure but the three LEDs stayed green? That doesn’t make any sense to me.
If my data is not protected, Drobo should indicate that by “don’t remove drive” which is flashing green/yellow.

We tried to make the device as simple as possible. Which means a limiting amount of LED’s and special configurations for those LEDs. There are only so many combinations we can do on the drobo and list on the faceplate of the drobo.

Unfortunately you are making this much more difficult that it is. You want to over simplify an already simplified system and it’s not netting you the result you want.

Green LED’s means your drives are healthy. You are putting the implication that they can be removed.

But you have to look at the health of your WHOLE drobo and ALL the LED’s with the IMPORTANT messages from Dashboard.

You had a combination of 3 solid green leds, 1 solid red led and a message from dashboard saying you were critically low on space and that your data was NOT protected and you needed to add a hard drive.

Why would you assume you could remove a drive in that combination? And please do not reiterate that the drive lights were green and that means you can remove a drive. Green lights ONLY means those drives are HEALTHY.

Well, it is that simple: flashing green/yellow means “don’t remove drive” so I as a normal customer think it is okay to remove the drive if that status is not indicated.

A red light tells me to add a drive here because Drobo is running out of space (>90% right?). It’s not telling me that my data is not protected (at least i thought that).

What’s the problem with flashing the lights if my data is not protected anymore? Do you think customers are complaining if the LED flashes green/yellow but they cannot hear any drive activity? As I said before, green/yellow does NOT say “rebuilding data”.

Another situation: Imagine I have three disks in my drobo and everything is fine (three green lights). Now I add more data and reach 85% usage… A yellow light will appear next to the empty slot, right?
I’ll ignore that and reach 90%. Now the LED will turn red and my data will not be protected anymore?! I cannot believe that… But that’s what you’re telling me.

Actually when you are critically low on space and have a drive that is solid red, you are not protected. Dashboard alerts you with the same message you saw when you removed your drive and caused the solid red light.

You are critically low on space, your data is not protected, please insert a hard drive.