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PostPosted: Wed Sep 10, 2014 7:29 am 
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Having used a Seagate 3TB GoFlex Home NAS Drive for over 1 1/2 years, it suddenly seems that yesterday I may have lost every piece of data on the drive. Nothing special happened but as usual when I logged in, I found the "sub-drives" X, Y, Z, i.e. Public, Backup and Personal showing about 80% full of data but the drive size showing only about 211 MB as against 3TB and free space 51 MB. Upon clicking, the contents are all gone, empty.

Before I did an RMA to Seagate (warranty valid till 2015) I thought I would rather first attempt retrieving data because it contains lots of important stuff: all local email backups, all software licences that I have purchased over the years, lots of personal information etc.

Problem is, no recovery software would work on a NAS drive unless connected by USB to the PC, unless I go out to a professional service company and get stripped but with no restoration guarantee.

I just happened to read in the User Manual of the GoFlex that the drive, if taken out of the dock, can be attached to another kind of Seagate dock called GoFlex Desk Dock that would enable me to connect the drive to my PC by USB directly. I just ordered it and am expecting delivery in 2-3 days.

Thereafter would start a marathon exercise of choosing the best software for the purpose, as I understand that the OS used by NAS drives is not Windows but is something like Reiser FS or Linux or similar.

The question therefore is, once I connect using the (yet to arrive) desk dock directly to PC, what software tool would be best to:

a) detect the drive and
b) extract data out of it.

The drive currently is making a sound as if something wants to turn but is not being allowed to and keeps doing it.

I know a few software tools but I am not sure which will work for sure. Basic understanding from a friend is that that Stellar Phoenix is advertised as the best, R-tt Tools is the best amongst the lot.

Would love you have an expert opinion or even better if someone has experienced a similar situation and the resolution if any.


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PostPosted: Wed Sep 10, 2014 3:38 pm 
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According to this blog, the GoFlex uses NTFS as filesystem. So your 'normal' Windows tools should work with that.

Quote:
The drive currently is making a sound as if something wants to turn but is not being allowed to and keeps doing it.
If your disk has a mechanical problem, you should first make a raw copy to another disk, and use that for recovery. Data recovery on a dying disk is just not a good idea.


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PostPosted: Wed Sep 10, 2014 6:09 pm 
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Thanks Mijzelf.

Just to let you know, I had sent the same post to Seagate community and I received an email as follows:

"When the drive shows 211MB it means that the linux firmware bind mounts are messed up and the root filesystem on the flash storage ubi0 is mounted instead of sda1. It seems to happen when there are filesystem errors on the hard drive.

Unfortunately you can't access a 3TB drive using the Seagate desk adapter as the usb bridge uses 4096 byte sectors and the drive is set up with 512 byte sectors. You would need to connect directly with SATA or maybe use a non-Seagate usb adapter.
The GoFlex Home firmware is Red Hat Linux, but the drive is formatted with NTFS. See link: http://davidvielmetter.com/tricks/seaga ... intenance/.


I did read the link at davidvielmetter.com but I also searched further and found another link which, I thought, in a way contradicts the davivielmetter.com link. This new link is: http://www.anandtech.com/show/3858/the- ... 3tb-review. The last but two paragraph is shown as a strikethrough, meaning, superseded and it reads as:

"Internally the drive uses 4K sectors however it translates to 512-byte sectors before it reaches the SATA port. This means to a SATA interface the 3TB drive looks like a drive with 512-byte sectors. The GoFlex Desk docks then map the 512-byte sectors back to the 4K format. There’s obviously overhead associated with these translations but it’s not huge in most cases. The final 4K translation done by the GoFlex Desk dock means that you can partition the drive using MBR which ensures Windows XP compatibility."

Then follows this update:

"Seagate offered some clarification to the paragraph above. Internally the 3TB drive uses 512-byte sectors, however the GoFlex dock emulates a 4K drive to allow for a single 3TB partition to be created in Windows."

Additionally I found this link:

http://www.anandtech.com/show/3858/the- ... b-review/5

So now going back to your suggestion, my first problem is detection of the drive itself. I tried inserting a sata cable, albeit with a little force but the drive wouldn't get detected. So hopefully the Dock is the right decision that I took and I do hope that the drive gets detected.

So I would then be in one of two scenarios:

a) Undetectable drive. What is the best option to get my laptop to recognise it?

OR

b) Drive detected but data invisible, like it is now.

Any views on the reply from Seagate forum? I tend not to like it, simply because it contradicts as above. I shall wait till the drive reaches me and I'll get back.


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PostPosted: Wed Sep 10, 2014 7:29 pm 
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I'm not sure which contradiction you are pointing at. David Vielmetter just tells the disk is NTFS formatted, and Anandtech tells something about sector sizes. That is no contradiction.

It is not really important what the internal sector size is. No matter what it is, the logical sector size is 512 bytes. The only problem the internal sector size can give, is partition misalignment, which can have serious impact on transfer speed.

The 4k sector size behind the usb bridge is a problem. This is a trick applied by most (all?) sata-usb bridges for disks larger than 2TB, indeed for XP compatibility. The 'classic' MBR partition table can store an 32 bit start- and endsector for the partitions. So the biggest endsector is 2^32, which is about 4000000000. If you multiply that with the 512 bytes sector size, you get 2TB.
XP doesn't support another partition table format, but it happened to support 4k sectors. Using the same partition table, the max partition size is suddenly 8 times as big, up to 16TB. Everybody happy.
The problem is that the disk was connected to a sata bus, which shows 512 byte sectors. (The disk has a GPT partition table to be able to handle 3TB). The partition start and end are given in sectors, so if suddenly the sector size changes, the partition is not where it ought to be. That problem could be solved by generating a new partition table, but possibily the filesystem internally also uses sector numbers.
So a disk partitioned and formatted on 512 bytes, has to be read on 512 bytes. An usb-sata bridge is not usable.

Quote:
I tried inserting a sata cable, albeit with a little force but the drive wouldn't get detected
Did you also power the disk? A sata cable doesn't provide power.
Quote:
a) Undetectable drive. What is the best option to get my laptop to recognise it?
If the disk is correctly powered and connected to an (e-)sata port, and yet not recognized, then it's dead. Only a data recovery business can possibly recover it. (BTW, 'not recognized' means here that your laptop doesn't detect the disk at all. A raw disk is recognized)


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PostPosted: Wed Sep 10, 2014 7:51 pm 
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Yes I did power it.

Well, an e-SATA port, isn't it the USB port with a label saying e-SATA? So if the SATA-USB dock is used, and is meant for the product (as Seagate claims) to be used with the Seagate drive, where is the problem?

Anyway I'll investigate further. Now that I've ordered it, I'd rather try it out.


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PostPosted: Sun Sep 14, 2014 4:19 pm 
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Joined: Wed Sep 10, 2014 6:57 am
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Well I received the Seagate Desk Dock but as noted by someone in this post, it too didn't work. At least I had the opportunity to notice the following:

1. Drive spins up fine, then starts clicking.
2. Drive shows in Device Manager and in Lost Volumes of Stellar Recovery and R-Studio softwares but zero size
I'm now stuck between saving the cost of a new drive (RMA warranty for 3 years) and the value / cost of data.

Drive needs to be sent for data restoration services, not DIY, unless someone on this forum has a better idea.

Turning out to be very frustrating each day.


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PostPosted: Sun Sep 14, 2014 6:58 pm 
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A clicking disk which shows up as zero size is bad news. That clicking is recalibration, which means the disk fails in positioning the heads. And as the disk belike has some own system data on disk, it cannot tell the size of the disk, so it shows up as zero size.

I hope you have backups.


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PostPosted: Sun Sep 14, 2014 7:43 pm 
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The whole issue is because I don't have backups of some critical files. Mainly emails and software licences, besides scans of my home mortgage. Originals are with the bank!!


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