Drobo 2 Gen : Taking forever to optimized data after a HDD failure.

Little history for my case.
I have 4 x 3TB HDD to my old Drobo 2 Gen.
At 21/06/2016 (three days ago), a red blink made my to replace one of the HDD with an new 3TB drive.
Straight after that, all four lights started to blink green and orange, and the Drobo dashboard was let in me know that “the data protection approximately will take about 116 hours”.
Since then, (three days later) the four little HDD lights still blinking (green orange), plus the green one of the disk activity is always on.
My mac (OSX 10.9.5) refuses to “see” the Drobo as a HDD and also the Dashboard utility (1.4.2) can not find any Drobo device.
So the real problem for me, is not the huge amount of time that Drobo need to do its magic data splitting, but the lack of information.
I feel totally blind.
I do not know if I should turn off my Mac or the Drobo. Should I reboot the system? Will this help at all or I should wait the full 5 bloody days? Did anybody else had similar problem? If yes, I badly need some positive feedback. Thank you all in advanced for your time.


hi yannis, i think it is still rebuilding - please wait and i post back with more info for you:[hr]
im not sure how much data you have on your drobo currently, but it usually takes about 1day per 1TB of data that you have on your drobo. (this can take a bit more depending on if something else was using the drobo at some point during the rebuild) so it is usually good to add a bit more time to play safe before trying any reboots etc.

usually the rebuilds will still have the drobo working and being accessible to dashboard and the computer (though in a few cases dashboard or the computer can loose access)

First of all thank you for your response.
The data in my Drobo was around 6.14TB.
Basically I had to switch them all off, (mac and Drobo), cause of a bad thunderstorm.
Today I’ve switched them all back on.
I can not mount the Drobo drive to my mac.
The utility app is working fine.
All the Drobo lights are flashing (green and orange).
The “data protection message” tells me 240 hours remaining. (Bloody hell)…
The HDD activity green light is off, but I can hear the HDD working like crazy.
Anyway, I suppose I should wait (from the beginning) for another 7 or 8 days to found out if my back up data is ok.

yeah we had some thunder storms here in the uk as well recently, and i sometime keep computer equipment off if theres a storm on the way to play safe (even with some surge protectors)…

i think the fact that your drobo lights are flashing to indicate a rebuild which is in progress (may just be the same rebuild you had before, and continuing), but this would usually be rebuild-related, rather than computer activity. (that is most probably why the activity light on the bottom is not flashing, but the drive bay lights are).

as far as i understood it, it looks like the onboard battery has preserved enough data to be able to continue the rebuild process (as otherwise you might have seen a different or error message), but it is good that you powered up again because the internal battery can only last so long, and is usually meant for temporary interruptions to power rather than full-wide lengthy loss of all power.

in the best case scenario, if we take your 6.14TB (and round it up to 7 in case some computer access was slowing things down a bit during your first post), and it we take that 7 to be approx 7 days, it may finish by friday or saturday.

the fact that dashboard can see it, is good, and it would be interesting to see how the “hours remaining” message changes in a day or 2, but even if somehow the rebuild process wanted to run again from the beginning to make sure protection was in place, i would try to leave it to finish if you can.

once the rebuild is complete and all is (ideally) solid green again, the only thing that may be needed, (especially bearing in mind the initial rebuild, plus an interrupted rebuild), could be a maintenance program to get the mac to be able to see it again, such as disk utility / cocktail, or another program called DiskWarrior (which while may not be free, it has been successfully reported to fix a lot more things than the default mac tools).

please let us know how things go with the rebuild though and i keep my fingers crossed for you not getting any more storms :slight_smile:

Paul, I’ve got some news (not necessarily good).
After a full day of rebuild, the hours of the utility window wend down to 106, (witch sounds about right to me), but then again Ive lost connection with my mac (thru utility app).
The four little HDD lights still blinking (green orange).
I’ve got no time machine or any other kind of automatation to a back up to the Drobo, so I do not think that it should take more time than the 106 hours.
Should I wait the 106 (I hope) blind hours or I should try to hook in up to another Mac with different firmware (older or newer)?
The problem is that the weekend there are some more thunderstorms coming.
Should I wait for another day or it will start right from the beginning after reboot?
I want to ask about another thing.
Often, when I don’t use the Drobo I have it unplugged by the power, mostly for security reasons. May that causing the death of the internal battery?
Is there any reason to check it out (by the utility app perhaps)?
Can this be the reason of loosing the connection via the app utility?
I suppose that was more than one thing to ask…LOL
Thank you Pau for sharing your knowledge.

oh no not more storms :slight_smile:

if the previous storms were less severe then the ones on the way, and if the previous ones did not cause any powercuts for you, it might be an idea to actually keep it going for now, or up until the last moment for the storm to pass…

i say this because if it does have a chance to finish tonight or tomorrow, you might be able to let it finish and then shut it all down in time for the storms.

if dashboard or the lights are blinking are indicating a rebuild, then i dont think you will be able to speed anything up by connecting it to another computer… the rebuild will most likely always still need to take place and complete… if though, you are trying to access or copy a few specific files that you would rather have sooner, than later, then yes you could try connecting it up to another mac to see if it lets you mount (but in some cases the drobo will not present itself to a computer or dashboard, until it finishes a particular process, or gets to a certain stage).

for the internal battery question, as far as i understand it, the battery is pretty much just there to help store data for an operation to complete in the event of a sudden power loss at the point of the operation/transfer of data etc, and that when power comes back up (such as when a company switches over to another power source, and power is lost for a few seconds or minutes and comes back up), the operation can continue.

i dont think there is any risk in you safely shutting down the drobo and then powering off when you dont need to use the drobo for a long period of time, (or even overnight if that is the case) because when you shut it down, you are not really using the battery to store anything, and as far as i know the battery will either last for a long time or be recharged when the uit is next powered up.

the only thing i remember reading on another page here, is that if the power is out for a considerable amount of time, i think like a couple of days or something similar (as was mentioned for an older model), (when it was doing something) or if the battery was old and could not store the data or where a particular user kept it switched off for a week (when it was in the middle of doing something) only then does the main risk rise.