MediaSonic external drive now empty
Working with a MediaSonic 4Bay USB device configured as RAID 5 with (4) 2TB drives.
User has stored a lot of data on it over the last several months.
It shows up on the system as the w: drive.
Yesterday, he went to access it, and all it would display is a folder labeled "System Volume Information."
There are no red lights on the fornt panel. User reports one orange light... but I have to wait for them to return to their office to confirm which one it is.
We have tried restarting the unit.
We have tried restarting the PC
We have powered the unit down. unplugged it from the PC, then powered the unit on... then plugged in the USB cable.
None of the above had changed anything.
In windows explorer, if I right click on W: and select properties, it shows a total of 8T unused... and only 315 MB used (the size of the System Properties folder.
If I go to disk management it shows as as
New Volume (w:)
8383.28 GB NTFS
Healthy (Primary Partition)
NOTE 1: This unit has a button on the front top right panel that you can hold down for three seconds and change the RAID mode. NOTE: holding a button down is not an uncommon means of shutting a piece of hardware off.
I suspect user tried to power off the unit by pressing this button.
Any other explanations or recovery ideas anyone can suggest?
User has stored a lot of data on it over the last several months.
It shows up on the system as the w: drive.
Yesterday, he went to access it, and all it would display is a folder labeled "System Volume Information."
There are no red lights on the fornt panel. User reports one orange light... but I have to wait for them to return to their office to confirm which one it is.
We have tried restarting the unit.
We have tried restarting the PC
We have powered the unit down. unplugged it from the PC, then powered the unit on... then plugged in the USB cable.
None of the above had changed anything.
In windows explorer, if I right click on W: and select properties, it shows a total of 8T unused... and only 315 MB used (the size of the System Properties folder.
If I go to disk management it shows as as
New Volume (w:)
8383.28 GB NTFS
Healthy (Primary Partition)
NOTE 1: This unit has a button on the front top right panel that you can hold down for three seconds and change the RAID mode. NOTE: holding a button down is not an uncommon means of shutting a piece of hardware off.
I suspect user tried to power off the unit by pressing this button.
Any other explanations or recovery ideas anyone can suggest?
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actually, my last comment is wrong but shows something weird : 4x2To raid 5 should produce 6To and not 8To. so it would seem the raid was rebuilt as raid0. depending on how the fs was created, data may or may not be recoverable. maybe the appliance can let you rebuild the raid 5 without destroying too much data...
ASKER
skullnobrains,
My thought exactly... now showing 8T (4x2) so RAID was rebuilt. Checking with manf to see if possible to rebuild array.
My thought exactly... now showing 8T (4x2) so RAID was rebuilt. Checking with manf to see if possible to rebuild array.
let us know. beware that rebuilding the array the normal way will wipe the data, if by chance it is still recoverable (creating a raid0 or disk concatenation could have been done without wiping everything so the data might still be there. recreating a raid5 will most likely erase all existing data)
honestly, even if you manage to know exactly what the users did and are helped by the vendor, i doubt you will manage to retrieve much.
if you really want to go that way, you might be lucky enough to be able to create an unformatted raid within the appliance but this is quite unlikely
if not, you'll have to know what hardware raid card is in the appliance, and grab some specs, or possibly what software raid they used and use a separate machine to try and rebuild things manually
honestly, even if you manage to know exactly what the users did and are helped by the vendor, i doubt you will manage to retrieve much.
if you really want to go that way, you might be lucky enough to be able to create an unformatted raid within the appliance but this is quite unlikely
if not, you'll have to know what hardware raid card is in the appliance, and grab some specs, or possibly what software raid they used and use a separate machine to try and rebuild things manually
You can try to play with RAiD Reconstructor from runtime.org and try to emulate the RAID5. At least you loose nothing if you try it.
ASKER
Thanks to all for the replies. The manufacturer also recommended some tools and services. Will have to review with the user which way they want to go$$$.
What is odd, to change the RAID setting you really have to be deliberate in which buttons, how long, and what order you push them. Extremely unlikely this was an accident by the user or a cleaning person.
I checked with the manufacturer and they advised that an alternate scenario (holding the raid button down and then powering down) would not change the RAID button.
So how did it get changed? I am going to check their forums to see if there are any other cases of this happening. will report back with what I find there.
What is odd, to change the RAID setting you really have to be deliberate in which buttons, how long, and what order you push them. Extremely unlikely this was an accident by the user or a cleaning person.
I checked with the manufacturer and they advised that an alternate scenario (holding the raid button down and then powering down) would not change the RAID button.
So how did it get changed? I am going to check their forums to see if there are any other cases of this happening. will report back with what I find there.
ASKER
Additional info. I checked the forums for this device and found that others who were using RAID 5 for this 4 bay device were encountering the same issue. The manufacturer claims that this is due to the users not using enterprise drives that were all the exact same manufacturer and identical specs.
They sell this device as an empty housing. On the Specs on the website they say:
"Note: Mediasonic strongly recommend user to intall same capacity / model / brand of hdd." (SIC)
Please note that nothing is said about "must be" or that they are have to be enterprise drives but in their forum postings they advise that non-enterprise drives will break RAID 5 - and that is then the users fault.
There are plenty of RAID devices that do not require this... after all, drive models are discontinued over time... so what do you do, trash the whole NAS because one drive dies and you can't get the exact replacement?
The only good news is that I recommended that this device be returned when the user first brought it to the office. Live and learn.
One of the recovery services has advised that they "should" be able to recover the data... if they cannot, there is no charge. If they are successful, it will be about $750. Needless to see, we will not attempt this until we have a reliable device ready to take the data off.
Other companies had various tools you could use, but it is more challenging as this is a USB device, rather than an NAS.
Thanks to everyone for the suggestions. I will be splitting the points, hopefully as equitably as possible.
They sell this device as an empty housing. On the Specs on the website they say:
"Note: Mediasonic strongly recommend user to intall same capacity / model / brand of hdd." (SIC)
Please note that nothing is said about "must be" or that they are have to be enterprise drives but in their forum postings they advise that non-enterprise drives will break RAID 5 - and that is then the users fault.
There are plenty of RAID devices that do not require this... after all, drive models are discontinued over time... so what do you do, trash the whole NAS because one drive dies and you can't get the exact replacement?
The only good news is that I recommended that this device be returned when the user first brought it to the office. Live and learn.
One of the recovery services has advised that they "should" be able to recover the data... if they cannot, there is no charge. If they are successful, it will be about $750. Needless to see, we will not attempt this until we have a reliable device ready to take the data off.
Other companies had various tools you could use, but it is more challenging as this is a USB device, rather than an NAS.
Thanks to everyone for the suggestions. I will be splitting the points, hopefully as equitably as possible.
a piece of advice for the future
- build your own NAS if you have the knowlege (not that complicated)
- if not or if you need a nice web gui for your customers, buy the hardware and run something like freeNAS on top of it
- if you still can't do this, use products from a vendor that uses regular software raids and does not idiotically store the raid information at the beginning of the drive where the mbr and partition table should be. there will be much less chances to have such a bug on something widely used, and data recuperation will be much easier if the appliance breaks.
- do NOT use raid5 unless you really have a reason to do so : it is slow, quite insecure, and does not provide much more disk space than a raid 10 setup when you only have 4 drives
- use identical drives whenever possible when you are doing RAID, whatever the RAID level or vendor claims. ZFS has (AFAIK) currently the only volume manager that deals properly with mixed drive sizes and capabilities. appliances usually use either hardware raid or linux's software raid5
- build your own NAS if you have the knowlege (not that complicated)
- if not or if you need a nice web gui for your customers, buy the hardware and run something like freeNAS on top of it
- if you still can't do this, use products from a vendor that uses regular software raids and does not idiotically store the raid information at the beginning of the drive where the mbr and partition table should be. there will be much less chances to have such a bug on something widely used, and data recuperation will be much easier if the appliance breaks.
- do NOT use raid5 unless you really have a reason to do so : it is slow, quite insecure, and does not provide much more disk space than a raid 10 setup when you only have 4 drives
- use identical drives whenever possible when you are doing RAID, whatever the RAID level or vendor claims. ZFS has (AFAIK) currently the only volume manager that deals properly with mixed drive sizes and capabilities. appliances usually use either hardware raid or linux's software raid5
restoring the data of a raid 5 array from a set of drives without recreating the raid manually somehow does not seem feasible to me
i guess the appliance lost at least one drive. worst case scenario, 2 drives were lost and the appliance rebuilt a raid0 or raid1 on the remaining drives