Help Needed for Directory Recovery

I have a directory tree that contains subfolders with PDF and JPG files. For months, the files were readable using appropriate software for their types, but now, cannot be opened successfully from any computer or application. However, I can copy the files locally, so there is some sort of EOF marker in place, but the copies are also unreadable. PDF repair tools used against the copies are unsuccessful.

The only thing that makes much sense to me is a process interruption since on rare occasion, a process gets stuck, or a dirty shutdown while copying a file to that particular directory tree.

I gracefully restarted the 5N twice, with no change to file readility.

Since the Drobo 5N is networked, I cannot use chkdsk. Is there another tool to check and repair NTFS disk integrity, or is it possible to attach a local PC to the ethernet cable, or would that damage the integrity of the file system?

Idea?
Thanks in advance!

“Is there another tool to check and repair NTFS disk integrity”

That would be no use, since the 5N isnt formatted to NTFS??? its NETWORKED storage

internally its volume is formatted as ext3

yes you can plug the 5N directly to your PC using a network cable… but thats no different to connecting it to your pc via a router/switch and a network cable?

you can probably log into it directly (SSH) and run a linux disk check tool on the volume, but i’m not a linux expert so cant give you instruction for that, but you can probably work it out by searching the forum.

You would think the networked Drobos would have a “Check filesystem integrity” tool available from the dashboard, wouldn’t you? This is something that could be usefully implemented as a Drobo app, I should think.

actually most NAS dont have that, purely because it can lead to data loss

so they tend to assume that if you are smart enough to fully understand the risks of that, then you are smart enough to log in and run it from the command line

Drobos are different. They present a simple user interface and hide the internal working. They are designed to be used by people who don’t understand how they work and a lot of Drobo users are decidedly non-technical. By default there isn’t a command line available. You have to install Dropbear or OpenSSH to access it.

I’ve used a number of NAS systems and a filesystem integrity check is an integral part of all of them. The most recent (before the Drobo) was a Western Digital MyCloud which has a quick test and a full test, both available from the Dashboard.

To the OP…

Perhaps your file associations got changed. Can you copy a file to your local computer and open it there?

File associations?

if you mean this:

http://wdc.custhelp.com/app/answers/detail/a_id/10427/~/how-to-run-a-system-diagnostics-test-on-a-wd-my-cloud,-mirror,-ex2,-or-ex4

That’s not testing the filesystem, thats testing the drives themselves, which drobo does for you automatically on a monthly basis. (“quick” and “full” is a dead give away thats its a drive health check, not a filesystem check.)

From what i can find, there is no way to check the file system of the WD NAS units, but i am happy to be corrected if you can show me a link?

[quote]Selecting either method of the diagnostics will start the testing process and a Test in process progress bar will be displayed. The target of the diagnostics as well as the time it takes will depend on the type of test that is selected:
Quick Test: A quick test will take a few minutes, normally around 2, and will test the internal hard drives for major performance issues.
Full Test: A full test will thoroughly test each and every sector on the drives to ensure that the units are in peak state. This test may take several hours to complete, depending on the size and data configuration of the drives.[/quote]

Synology also has two differnet integrity tests - one tests the physical drives, the other tests the RAID array itself, verifying all of the parity. Neither of those test the actual filesystem used on the array. The only way to do that is to login to the Synology using SSH and run it from the command line…

Yes, that’s the one, Chris. The “full” option invokes fsck.ext4, which does indeed check the file system, the -c option also scanning for bad blocks. The “quick” option invokes a SMART on-line self-test which, I agree, gives an indication of the health of the drive and not of the file system. The two options therefore complement each other. Well done, WD. I’m curious to know what the Drobo does automatically on a monthly basis, though, and whether it could be triggered manually from a Drobo app.

Strange that the WD documentation doesn’t appear to mention that though? it only talks about checking the disk - basically doing a surface scan

Drobo’s monthly routine is a data scrub - it checks all blocks are readable and confirms the parity/mirror integrity. It does this during idle time, but does ensure that each slab is checked at least once a month.

The actual Filesystem presented by Drobo is contained within an iSCSI volume which is mounted by the NAS OS

Well, in my experience manufacturer documentation is pretty sparse and very much dumbed down these days. Inquisitive users are left to find out for themselves and hopefully share their findings. The MyCloud will run fsck on its system partitions (there are two, mirrored) on startup too if it decides it’s appropriate, though without checking the main user data partition or scanning for bad blocks, of course. I’m surprised you comment negatively about WD’s documentation while Drobo provides next to none itself. During the Drobo monthly data scrub, is there any indication (other than the sound of the disks spinning and of their actuators) that the system is not idle? Specifically, would you expect the activity light to come on?

hi i think it might be a good marketing feature, if the following was to end up being implemented…

“and drobo carries out an additional verification of your data every month in the background, to make sure it is protected and intact - and you can even check the status of this in Dashboard.”

whereby you could then see its status of whether it has verified the integrity of 100% of the data, or if it didnt finish verifying in the idle time that it had available, you could click a button to give Verification a higher priority and to resume its check further. either until completion, and to optionally self-standby, or to tell it to continue verifying for another 10% or similar.

that would be good, because there has seemed to be not enough (easily-accessible or promoted) information about scrubbing, for those who are seeking it, than too much for those who dont want to seek it :slight_smile:

(edit: tweaked wording above)

I’d go along with that suggestion, Paul. The Dashboard doesn’t offer much and what there is is mostly fluff. I could do without the pie chart, for example; a simple row of figures would suffice in exchange for some useful maintenance and monitoring tools.

ah yes, i guess ultimately, a lot of the features will always need to be present in the drobo itself (as they often run without dashboard) but sure some extra tools or info is always welcome.

i like the pie charts (in v1x and 2x dashboard) but then again i do enjoy eating pies too :slight_smile:

basically that is what it does paul. it ensures that it checks everything every month!

if its not idle enough, its increases the priority of the check.

it ALWAYS checks everything every month (assuming the damn thing is turned on)

youe idea goes completely against the whole idea of trying to keep drobo as simple as possibler

I think I’d like the option to have the technology of BeyondRAID but without the dumbed down user interface. I like to know what’s going on. Obeying red, yellow and green lights is fine only if you trust them and a lot of people in a lot of posts here have good reason not to trust them.

Where’s the technical information on this monthly scrubbing process, Chris? I haven’t managed to find anything in the knowledge base yet. Maybe I’m not looking in the right places.

[Edit] I found this one: https://myproducts.drobo.com/article/AA-01156 but it’s about as dumbed down as it’s possible to get. 1 star on the helpfulness scale.

previous posts by drobo emplyees on the forum

Ok, I’ll keep looking. Thanks.

thanks for the info docchris (thats another teacake i owe you) :slight_smile:

i guess as long i keep it on for 1-2 days each month, it can do its scrubbing :slight_smile: