Drobo

Gen2 started having problems - is it just time?

I would have posted this to Legacy, but that category doesn’t allow "New Topic"s it seems.
Almost a year ago, My Gen2, 4 slot Drobo started having troubles, though I didn’t know it at the time. It had gone into Data Protection several times, and eventually, in January, showed a bad drive. That drive was a 6 yr old 2TB, so, okay, it’s due. I replaced it with a new and 4TB drive. It rebuilds. All seems fine.

Then just less than a month later, another drive fails - also a rather old 2TB one. Odd, so close together, but I again take the opportunity to get a new/larger 6TB drive. It joins the happy group and I go on. But, keep seeing Data Protection to the point where I rarely see all green lights. Plenty of free space.

Then in May, the newest, 6TB drive fails (as reported by the Drobo red light). Starting to not be happy with the lack of any information other than working/failed - I’d like some data! But, it is under warranty, so I return (actually, it was, but WD said it was sold bulk, but I convinced Amazon to take it back.) I replace it with a Seagate Ironwolf 6TB. I keep having Data Protection problems and finally around late July, it goes into data protection, Drobo Dashboard can’t find anything and I wait and wait, for 2 months. Finally, I unplug it and replug it and it remounts and within a couple days, finished data protection, but almost immediately, goes back into it (same day). It recovers, but within days, the 6 TB drive starts flashing RED and Data Protection again. That clears and almost right away, another drive turns RED. No data protection because, not enough drives, so I just unplug it to stop the carnage.

So, is this just how Drobo eventually fails - it starts taking out all the data and drives? Or is maybe the power supply flaky and these are false failures? The lack of a LOG to tell me what has happened is disconcerting. I appreciate the intelligence built into this device, but having only “idiot lights” to communicate status to me is no good.

I have been considering a new 5N (or 2) so I could share it on the network, but I worry that my ability to see status on that would be even worse. Speed seems the other issue, but for backup that seems it would only affect the initial loading.

Comments or shared experiences anyone? I’m down to just my TImeMachine backup until I resolve this.

I think the Gen2 is running on borrowed time just due to age. Electronics don’t last forever. I still use my Gen2 at work as an offsite backup for my 5N2, and I have a 5N in the closet.

There are some drive makers who are now using SMR technology to increase capacity on hard drive platters, and SMR isn’t compatible with any RAID devices like Drobo due to poor behaviors which tend to be interpreted as drive failures. Perhaps you are using SMR drives and not even know it?

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Thanks. I certainly could be using SMR drives since I don’t know what they are. One of the drives I bought was for NAS, so I figured that would be a better quality. Guess I have some learning to do.
Love the Max avatar!

I have a Gen 2 - which has served me nobly. One of the drives (WD Caviar 1TB) went red and I replaced it with a 4TB WD.
As soon as I did this, the Gen 2 said it would take 51hrs to complete Data protection & then promptly disappeared from Drobo Dashboard & unmounted. Orange/Green lights have been flashing for a 8 days now; can’t mount or use the Gen 2 and am getting concerned that something has gone south.
I just want to transfer off the stuff I need and then I can send the Gen 2 to the happy hunting ground.

Any kind words or constructive advice, would be helpful pls?

BackGround:
4 Bay Gen 2
2tb
1tb
1tb
1tb (replaced this with the 4tb new drive)
Blu lights: 6/10 are lit (I’m assuming there’s lots of space, now)
OS is OSX, El Capitan
Drobo Dashboard is the last one it can take: 2.6.4 I believe
Connection is via firewire 800

Which 4TB WD? The Reds are now SMR at that capacity, you need Red plus or Red pro to get PMR in 4TB allegedly “NAS” drives from WD.

Can’t see it right now, as it’s in the 4th bay with the lights are flashing. But I know it’s a 4TB green barracuda.
All my drives are green.

I couldn’t find information on the Drobo site when I was buying it and all I remember finding was that the Gen 2 Drobo could only accommodate a max of a 4TB drive in each bay.

I should add, that my Drobo is DAS, not NAS

From the current manual on the Seagate website for their current (Non Pro) BarraCuda Hard Drive 4 TB ST4000DM004 model:

Link: (seagate.com)

2.4 Recording and interface technology

Interface                              SATA
Recording technology                    SMR
Recording density (kBPI)               2294
Track density (ktracks/inch avg)        540
Areal density (Gb/in2)                 1203
Interface transfer rate (MB/s)          600
Data transfer rate (MB/s)         up to 190

That “Recording Technology” is the killer …

For Reference
Maximum Volume Size and Largest Size Drive (drobo.com)

Choose Drive - Drobo

In the third table at the bottom they’re recommending either BarraCuda Pro or IronWolf Pro from the Seagate range.

It’s getting a bit of a minefield straying outside that matrix unless you dig into product manuals & spec sheets the way SMR is proliferating silently. Drobos tend to misbehave with SMR drives.

Currently the IronWolf (non pro) drives are conventional recording if you’re matching existing slower rotational speed existing drives.

My units are both DAS too, but NAS drives make sense given the workload.

I’m not sure how one recovers from an SMR drive being put into a pack & the unit misbehaving during the rebuild, my gut feeling suggests shut down, remove entire pack, clone any SMR drive to a CMR/PMR one, then substitute the clone into the pack, load it up & start the unit.

Either that or swap it out for CMR/PMR reset the Drobo & restore data from backup.

The good news is I think the unit itself is fine, the bad news is I suspect that 4TB drive is SMR & no good for use in a Drobo, that’s only opinion without exact details of the drive model & serial at this stage though.

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I wonder if Drobo has any plans to accommodate SMR drives in the future? Seems they will need to or else they will become irrelevant since the new largest drives are all SMR and the cost/TB of those makes them compelling. Not that it is matters lately since Drobo hasn’t had any product for sale for the past half a year. I was ready to buy one back when I first posted this thread, but not so sure now. I bought an 8TB drive so cheap that I can just use SW to mirror those and have more than my old Drobo had with 4 drives that were smaller CMR drives.
I unplugged my Gen2 months ago after copying everything off, so it wouldn’t degrade further. It served me well for about 8 years.

“Can they” & “Should they” are different questions, It’s a bad idea to use SMR drives in any sort of parity RAID, the performance during a rebuild is so poor by virtue of the properties of the drive itself, the chances of more failures during the rebuild go way up. Setups using mirroring are more forgiving.

There are good reasons why enterprises who do “real” RAID use enterprise class drives in their arrays, and why most NAS drives remain CMR, WD plain Red being the exception, & that caused so many issues not only with Drobo they reintroduced the old CMR Reds as Red Plus.

Be aware, simply unplugging your Gen2 won’t stop capacitors ageing in the PSU in particular, though it might save wear on the drives, & I’d power it up occasionally to run chkdsk /scan or other test of the data integrity to mitigate against bit-rot.

Update (edit):
@Rossta0825 If you look here you’ll find SMR drives are also problematic in Synology & RAID-Z setups. Basically they’re unsuitable for RAID/NAS enclosures that use parity based arrays no matter what WD’s marketing bods claim about the base Reds.
At least if you visit the current iterations of Seagate & WD’s websites the info on what technology is used (CMR/PMR vs SMR) is actually now available for a given drive model.