Drobo

180 hours to rebuild?

Support ticket is 091201-000078 in case anyone at Drobo wants to see my logs. I’m sure the person on my case has gone to bed for the night but I want as much input as I can get.

I have a Drobo Gen 2 on Mac OS X formatted HFS+ via FW800 to my Mac Mini. FW 1.3.5 Dash 1.3.1

I had 4 1.5TB Drives in it, and it had 3.5TB of data, and went yellow warning me to replace drive 1. I did so, replacing drive 1 with a 2TB Caviar Green, and it said it would take 180 hours or so to rebuild. I contact Drobo, they gave me a bunch of steps to try, and I did. Same result. So I think, ok, its a bad drive. I stick my old drive, which worked fine, back in and its still saying 180 hours. At one point it even said 320+ hours.

Any ideas?

[quote=“jfield, post:1, topic:787”]I had 4 1.5TB Drives in it, and it had 3.5TB of data, and went yellow warning me to replace drive 1. I did so, replacing drive 1 with a 2TB Caviar Green, and it said it would take 180 hours or so to rebuild.
[/quote]

When I replaced a 1TB drive in my Drobo V2, it took close to 3 days.
I thus computed that with 2TB drives full, relayout would take around 6 days.
Your 180 hours makes 7.5 days, so if there is any non-linear component in the relayout process, I suppose it is more or less compatible with my ball park figure…

Now, although “normal” like “it is coded that way”, I am probably not more happy with those figures than you are. If you consider that during this full week you have ZERO data protection, while at the same time having a much higher probably of defect on one of the 3 remaining original drives, due to intense relayout I/O activity, that is truly frightening.
DRI is completely aware of that weakness : Drobo-S, with a 5th drive, Dual Disk Redundancy and background data scrubbing utility precisely corrects it.
Too bad DRI “Customer Loyalty program” only offers a paltry 6% rebate to Drobo original customers stuck with a sub-optimal design and wanting to upgrade…

7.5 days is in fact just about right. I just went from 7 -> 8 Tb in my first-gen Drobo, by replacing the last 1Tb drive with a 2Tb Caviar Green, and it took right around 7.5 days to rebuild.

thats very long time, it should be 48-60ish hours max.

however - anything using/indexing your drobo will dramatically slow down its rebuild time

Thats a good point - I’ll try adding it to the Spotlight exclusion for now, and make sure nothing else is accessing it.

I really love the drobo but I really hate the single disk redundancy. I guess I’ll be forced to pay the insane price for the Drobo S when it shows up somewhere I can finance it. =/

That said, I’ll wait to hear back from Drobo re: my logs before I start to rebuild it again.[hr]
Now it just tells me to replace the 2TB drive with a larger drive… but I just used IT to replace a 1.5TB, and it hasn’t rebuilt yet. My trust in this product is completely destroyed at this point.[hr][hr]
Last question, while rebuilding should I see a steady light on the activity light, or is that only when it transfers information between it and the computer?

Replacing only one of your 1.5TB drive by a 2TB drive will give you ZERO capacity increase (check the Drobolator).
You need to replace (sequentially) a minimum of 2 disks to see an increase (of 0.5TB). That’s 7 more days without any data protection…

Welcome to the club; your first painful drive upgrade does that to too many Drobo users…

geeji - its telling him to replace his 2Tb drive with something larger tho - that is indicative of a problem, if it were just an overall lack of space, then of course it would tell him to replace the 1.5tb with a larger drive.

if you have 4 x 1.5tb and its low on space, it will prompt you to replace a drive with a bigger one, so you do… and it has exactly the same space still so ti prompts you to replace ONE OF THE REMAINING 3 x 1.5tb drives it would NOT ask you to replace the 2tb one with a bigger one because this woudlnt solve anything (as you know)

Yeah it has been running since 8AM EST this morning and has 287 hours left. The sliver of progress has gotten (slightly) bigger, but I have no faith that it is actually rebuilding anything.[hr]
Also Drobo support told me to stop pulling diagnostics because it restarts the relayout process. Why would that be the case? And why wouldn’t you warn users that a seemingly harmless menu option can make a ridiculously long process even longer?

@jfield

Did you want to discuss your case on the forum or through your case?
I am the owner of your case.

Just trying to get as many opinions as I can on this, its very important to me. I have backups but I’d rather not have to use them. We can continue through the case. Right now I’m just checking in via VPN every hour or so to see what the rebuild is at. It finally is down to 80 hours which, while unacceptable to me, seems normal.

[quote=“Docchris, post:7, topic:787”]
geeji - its telling him to replace his 2Tb drive with something larger tho - that is indicative of a problem, if it were just an overall lack of space, then of course it would tell him to replace the 1.5tb with a larger drive.[/quote]

Yes, I know, but unless there is a bug in the Drobo software, why would the Drobo ask for a LARGER disk than the one already largest, instead of suggesting replacement of one of the smaller ? And if it is a simple disk failure, why should it require a “larger” disk, especially since increasing the capacity of the largest disk only does not increase Drobo capacity at all ?
When I upgraded my almost full Drobo from 1TB->2TB on 2 of my 4 disks, I had plenty of problems and Drobo had very peculiar ideas of which slot should have its disk replaced (usually slot #0 and sometimes #3).

like i said, its indicitive of a problem somewhere, he should open a support case and submit a log as this is not expected behaviour

Right but running diagnostic files during relayout is not really an option. It restarts the rebuild process and usually will cause the drobo to reboot which is a bad idea when it’s in the middle of the relayout process.

  1. thats fascinating, ive never heard running diag restarted a rebuild

  2. if I’m reading it right, its not rebuilding, its just sitting there asking him to replace his 2Tb drive with a larger one

Yes it will restart the rebuild or cause the drobo to crash. We would never ask for a diagnostic file to be performed while in in the relayout process.

It is rebuilding, it’s in the relayout process.

I can confirm its rebuilding, 54 hours left. Is this normal for a drobo full of 1.5TB drives? Is there anything I can do in the future? Is it because I let it get too full before swapping the drive or something?

Yes it’s normal.