Drobo

Drobo critically low on capacity

I am running a Drobo S on a Mac OSSierra system. I have total disk storage 9TB which reports as 6.16TB available capacity under the Dashboard. Looking at the files stored on the Drobo this amounts to less than 4.5TB. That being the case why am I getting a red light on the smallest !TB disk & Dashboard reporting I have used all but 98% (6TB) of the available storage?

hi spk,
would you be able to post back with some more info about the drives and sizes you are using when you get a chance?

for example, do you have drives such as these: 3x2TB and 3x1TB (in single, SDR drive redundancy mode?)

I have 4 x 2 TB & 1TB thus a total of 9TB in drive terms. Confirm the Drobo is set for SDR

Thanks for your assistance on this

thanks for the info spok10128,
with this in mind, it looks like you have the following drives set-up:

2TB + 2TB + 2TB +2TB + 1TB = 9TB Raw capacity
9TB - 2TB (for sdr using an equivalent size of your largest drive) = 7TB Actual
7TB (*0.9 for filesystem overheads) = ~6.3TB available (though probably better at just over 5.9 used)

the 6TB you mention above, seems to match ok, and i think at around 5.9TB used will be the mark where it is 95% used… it is this 95% used which is the threashold for showing a solid red light, usually on the smallest drive (which matches up with your 1TB drive being marked in this way if i understood correctly)

there is another Yellow threshold which shows a solid Yellow when you get to about 85% used, though am just wondering if you could double check how much data you actually have on your drobo, and also whether the blue lights on the bottom are almost all lit up, possibly 9 or all 10 for you currently?

for example, where did did the 4.5TB used, come from? (are there possibly any other volumes containing data, or maybe some other hidden files and folders taking up space on your drobo?

could you also check what values dashboard shows you for Used space and how many volumes it sees? (you could also try taking some screenshots and posting to imgur or similar, with links pasted to them back here if you like, though if you do that please remember to rub out any sensitive/serial numbers before uploading to play safe etc)

As originally advised, if I look at the Drobo via Finder the visible data stored on the drive adds ups to approx 4.5TB (Backups 3.8TB, Media 510GB, Poseidon 81mb - see screenshot ref below). I confirm all 10 blue lights are lit.

I notice that the Drobo seems to be frequently self-dismounting - possibly some self protect mechanism when critically low on space?

As suggested I have posted screenshots on imgur at this link http://imgur.com/a/svoUE.

Unless there are some mysterious hidden files which might be deleted, the only obvious solution seems to be to replace the 1TB with another 2TB - though surely I’ll be in the exact same position in 3/6 months when that also fills?

thankyou for the screenshots,
sometimes the free space can update slowly in the background, (and could be that you do have less data now on the drobo though maybe something temporarily wrote to it, though if it has been the same like that all this time, im not 100% sure where the non-apparent data usage is coming from…)

what i would do if you can, would be to try copying some files onto your local drive (or somewhere else) which is about 4% of your used data. and then when you are happy that the copied files are all ok, to then try and remove those files from the drobo, to try and get the used value down to 94% before doing anything else.

then, once around that level of used space (or a bit less if easier) if you happen to have access to disk utility or diskwarrior (which is usually very good on macs) it might be worth running a check on the drobo using that. (just in case it find any lost and found files / or other errors just in case?)

once at about 94 (even if you can not run a diskwarrior check) you could then try removing that red drive (which may be the 1TB smallest drive) and then shortly after the drobo and dashboard should recogise the removal, and to put in the larger replacement like you mentioned, where it should recognise it shortly after, and assimilate it into the diskpack.

if you can then let thing settle down a bit, and to let us know how things go, we can try and see if there are any other funny things going on :slight_smile: (hopefuly things will be ok)

I have since managed to reduce the used space to 90%. I am running the Mac Disk Utility on Drobo though this has been running for approx 12 hours & not sure what progress is being made. I note your recommendation about Disk Warrior though at $150 I could buy a replacement 5TB drive. Are there any other tools you can recommend?

ah well done for getting it to 90, for the mac though i do not actually have a mac and am not sure which other tools could help you, other than the fact that diskwarrior is known to fix a lot of mac related problems even on internal mac drives…

but, just looking back at your original post… maybe another possible way forward could be this…?

  • what if you bought a new drive instead of diskwarrior, and tested the blank drive in a stand-alone non-drobo way to make sure it is ok,
  • and then if you copied all your data from your drobo onto it as a backup, which may just about fit all of your data. (and to verify etc)
  • and then to reset the drobo and format it from scratch
  • and then to copy your data from the new backup onto your fresh drobo (and verify etc)
  • and if all is well, you now have a drobo all working properly again, and you could either keep the 5TB new drive (for your own backups, or to wipe it and resell or to use in future as an upgrade or something…

just a thought but what do you think about this? :slight_smile:

[quote=“Paul, post:8, topic:143512”]
ah well done for getting it to 90, for the mac though i do not actually have a mac and am not sure which other tools could help you, other than the fact that diskwarrior is known to fix a lot of mac related problems even on internal mac drives…

but, just looking back at your original post… maybe another possible way forward could be this…?

  • what if you bought a new drive instead of diskwarrior, and tested the blank drive in a stand-alone non-drobo way to make sure it is ok,
  • and then if you copied all your data from your drobo onto it as a backup, which may just about fit all of your data. (and to verify etc)
  • and then to reset the drobo and format it from scratch
  • and then to copy your data from the new backup onto your fresh drobo (and verify etc)
  • and if all is well, you now have a drobo all working properly again, and you could either keep the 5TB new drive (for your own backups, or to wipe it and resell or to use in future as an upgrade or something…

just a thought but what do you think about this? :slight_smile:
[/quote][hr]
Still chewing on this, however, one question. I have other external drives which when used as Time Machine storage just overwrite older files when the disk runs out of space leaving me in an endless loop with the say 100 most recent backups. The Drobo does seem to be designed not to do this since when it runs critically low on space, to appears to prevent the Time Machine from performing any further backups. Do you have any knowledge of this?

ah there might be some settings that could help within time machine itself too… there was a very good site mentioned i think by johnm called pondini , for example here that might have useful info in general too:
http://www.drobospace.com/forums/showthread.php?tid=143858

is your time machine using a specially-created (limited) time machine volume that dashboard made, or is it just set to use a particular volume on your drobo (but that does not have any actual “limits” as to how much space time machine can use)?

The Drobo was never partitioned which might be part of the problem. What I plan to do now is move across my data plus the January/February Time Machine backups onto the iMac. I’ll then reformat the Drobo & partition 200gb for data & leave the remainder for Time Machine backups. I’ll continue reading through the link you sent. Do you have any other recommendations on this?

thanks for the info.

sure - am pretty sure that Only dashboard should manage volumes (or create any time machine-specific volume)… using any other tools on the drobo like to partition or defrag a drobo etc, can only lead to problems :slight_smile:

The only dashboard tools I find are format & volume (rename). How do I therefore go about partitioning the Drobo other than using the Mac Disk Utility?

ah i think this page may help:
https://myproducts.drobo.com/article/AA-01809
(i do not have a mac but that article from the knowledgebase seems to mention steps for a drobo-s with timemachine)

it mentioned dashboard needing to be at least v2.6.2 which will show a button for backups if supporting your model, there is also a page here, showing the example, but am not sure about the drobo-s:
https://myproducts.drobo.com/article/AA-01862
and here https://myproducts.drobo.com/article/AA-00911
these pages seem to indicate only for the mini, gen3 (or newer 5d models) so we may need to wait for some other mac users to help you further as i have never used time machine myself to be honest.

I had to address other related issues however, I am now ready to start the reformat, however, the linked instructions provided seem to set out the process for reformatting Drobo under Lion whereas I am using Sierra & the steps set out do not obviously tie up. Under Sierra the Disk Utility options are First Aid, Partition, Erase, Restore Mount & Info.

ah its possible that the older guides have become a bit out of date, but i am pretty sure that only dashboard should do the option (if it was to exist for a time machine backup)…

but i was just thinking, what if you tried something else which could maybe achieve your objective?
for example, what about those flat files (sparse bundle or fixed size file)?

if you were to create one of those, (say at a fixed filesize that you are happy to use up for time machine), then could that not essentially achieve the same goal, where time machine just uses that for its data, and as far as the drobo would be concerned, it would just be another (rather large) file that is stored on the drobo?

I was planning to report in today confirming that all had been restored - until I turned on my iMac…

I had previously removed all data from the Drobo & formatted using the Mac Disk Utility which did not work out since I was unable to partition. I subsequently realized there was a format option within Drobo Dashboard tools which worked as expected & I then partitioned using the Mac Disk Utility. I copied back the data to one partition & pointed Time Machine to the second. There was a momentary blip when the Drobo could not be found & I realized the green light on the right side of the Drobo front panel was flashing. I shut down the Drobo & once it came back up the backup started. The first backup completed after about six hours with hourly backups thereafter. All was good.

This morning on start-up the iMac could not find any Time Machine backup disk. Drobo Dashboard cannot see it, nor do any Mac tools (Finder/Disk Utility). I have shut down the Drobo & iMac repeatedly without improvement. The USB connection is undisturbed.

Any ideas what I do next?[hr]
Not sure what started the problem but the failure of the Drobo to mount was caused by my not following the correct shut down/restart procedure. Drobo now again detected & backing up Time Machine.

ah thanks for the update (and 2nd part of the update) with the better news :slight_smile:
fingers crossed it will continue to be ok for you.

I do have a continuing issue. The iMac to which the device is attached is scheduled to shut down overnight & autostart in the morning. Since this recent re-formating/partitioning, the Drobo constantly fails to remount on start-up. I am now compelled to shut everything down & restart in sequence, after which the Drobo runs fine throughout the day, until the following morning when I am again required to restart the iMac & Drobo.

Any ideas what I should do to correct this?

hi spk10128,
would you be able to try disabling the scheduled shutdowns and restarts of the host computer, at least for a few days if possible, just to help make sure that it keeps working if the host is not restarted?

if you need the host to shutdown and restart every night, then maybe there is a way to schedule the drobo dashboard to shutdown the drobo first, before the computer is shutting itself down…(there may be a way to do this on the mac via ejecting if that is ok to do, but a 3rd party tool might be needed to simulate the mouse clicking on dashboard to shutdown) - but when you restart the computer (even via the schedule), will the drobo boot up as normal again?

if it is ok for the drobo and computer to be running all day, another option could be to try leaving them simply running each night as well, (at least as a test). from an energy point of view, am sure all the extra hours of potentially un-necessary hours could add up (even though there are some spin downs of drives in some models or power saving features of computers - which are not without their own problems too), though in the long run, if it is safe to do so, keeping them running 24/7 will probably be better then starting and stopping every day. (at least thats what ive noticed over the years and 2nd hand experience)