Drobo

Power failure during relayout

Just wondering what would happen if there was a power failure during a relayout/rebuild?

best case: nothing happens and relayout continues once power resumes
worst case: your data is screwed and you can no longer mount the volumes

take your pick :wink:

Here’s a better question, because it’s what I’m going through right now.

Let’s say there’s a known bad drive in the array that drobo would like you to remove (not dead, but hanging/stalling). Then the drobo initiates a rebuild. Do ALL lights on the front flash green/yellow, or does the failed drive light continue to blink red while all the others flash green/yellow so that you can replace it?

@ idobi - DRI’s official statement is that they always see SOME data corruption if power goes out in a rebuild

in my personal experience - its happened to me twice - chkdsk found and fixed a few minor file system things, but i never found any corrupted files (im sure one or two may have - but i havent noticed anything!)

@rkuo: Only the drives in use will flash green/yellow, meaning the bad drive (red flashing) will remain flashing red.

Thanks … that helps. I was wondering if the Drobo was poorly done in the sense that it would flash everything yellow/green even with a bad drive in there. So the Drobo must be marking my drive bad temporarily and then bringing it back online before rebuilding.

Can you do a safe shutdown through the Dashboard in the event of a power-failure during a relayout, assuming the Drobo is attached to a UPS? Or is there a way to configure this automatically? If not, this seems like a rather glaring oversight.

i think drobo ignores shutdown commands during rebuilds…

but im not about to test it

Can somebody from DRI chime in here? If power failure during a relayout almost certainly corrupts some data, yet the only line of defense against that is a UPS, which wouldn’t last a full relayout, is there a way for the unit to safely shutdown then during relayout? Or are you working on such functionality in the future?

I recently had a power outage while my DroboPro was rebuilding (attached to a UPS). Although it would not shut down from the panel, I pressed the on/off switch on the back of the unit, and it gradually shut down (not an instant shut down). Later I powered the unit back on and the rebuild continued.

That’s encouraging (I should really buy a UPS), but the Dashboard should have some functionality built in such that if it detects the power has been shunted over to a UPS, then it can start a graceful shutdown automatically since it knows the UPS won’t last.

yeah - the pro’s are slightly different due to their hardware power switch

there is no actual reason why you shouldn’t be able to tell it to shutdown during a rebuild - it should just carry on when done

Thats typically a bad practice Sunny, in the case of a re-layout you would NOT want to interupt that process unless absolutely neccesary.
Since you have it connected to a UPS, you would have been better to just let it run.

You ended up ok, with the re-layout resuming, but I personally would not want to chance my data.

Just a best practice.

Rmeyer, seems to me his point was that since the Drobo is not UPS aware and cannot be told to shut down during a relay, Sunny just speeded up the inevitable although I would certainly have waited to see if God intervened in the interim and restored power :slight_smile:

(He did the wrong thing but DRI is more guilty of poor design, especially if they suggest that power downs during relays generally end badly, as Docchris suggests in reply #4).