Synology Disk Station DS-101g+ - What file system is this?

[zed]

Hi All,

I have a Disk Station DS-101g+ NAS box reporting a degraded disk. This is a single drive unit with 1 sata disk inside.

The disk has no bad sectors or hardware faults. For some reason the NAS box cannot see the disk's file system or repair it. It simply states 'HDD Failed'.

I have removed the disk and tried to view the disk using many tools, i am unable to determine the file system. I believe it may be a modified version of ReiserFS.

Has anybody here ever recover data from one of these units before? If so - what program would you suggest?

X-Ways, R-Studio, UFS Explorer, Stellar Pheonix/Kernal Liniux products fail to see the partition.

Any tips on a way to recover the data? I suspect the partition is corrupted or damaged.

Thanks for any help.
Zed.

[BlackST]

If not proprietary filesystem, I suggest searching for Linux partitions. Many of there NAS systems have an embedded Linux as OS. Can you find some trace of a "known" filesystem reading at low level the sectors ?

[zed]

BlackST, i'm afraid UFS, X-Ways and R-Studio cannot find any recognisable file system. I assumed it would be ReiserFS or Ext2/3 like most NAS's but none of the programs i use can see it or browse to see any files. In hex view the raw data is there but unsure how to pull the data off.

I tried to clone the disk then run a repair in the NAS unit bit it could not repair, only gave the option to reformat.

When i search for lost partitions by scanning the whole disk it only find 2 small linux ext3 swap volumes (e.g 100mb, 300mb size) but not the large partition which is still unknown.

[BlackST]

Suggestion : get another disk, put it in the NAS and format it with the NAS unit, then put some files in it and analyze THIS disk.

[zed]

Good idea. I'll give that a try and let you know how things go tomorrow.

[BlackST]

It's not for free... I'll PM my address, please send beer, 1 barrel...

[BlackST]

Update : according to a colleague this NAS uses EXT3 or FAT filesystem but to be confirmed.

[zed]

BlackST. i don't think it's a EXT or FAT. UFS Explorer scans the disk and detects is 'SNAPOS' but this does not work either. I believe it's a customer version of ReiserFS which none of the standard tools seem to work with.

[thatdellguy]

Different file systems will write there type to certain sectors at the begining of a drive. Read the first 100 sectors with a hex editor. Some other file systems may be further out. It may give you a clue as to which file system you have.

[zed]

The starting sector looks like this:

Attachments

[thatdellguy]

What about sector 63?

[thatdellguy]

[zed]

That's actually starting at sector 128, 0-127 are blank.

[TerraNova]

defintely EXT3 fs

[zed]

X-Ways, UFS Explorer and R-Studio (latest version) cannot detect this disk as a EXT2/3 (or even ReiserFS).

TerraNova, what makes you so sure it's really a EXT3?

[N.C.]

Hi, Zed

I think, none of the manufacturer are enoug crazy to write own fs, because a lot of open source and good working, fine optimalized fs are available.

U should try to repair the clone.
Try to find secondary or another superblock by various fsck tools.
Did you try XFS?
If i think right, the xfs is the best choice for NAS box.....

Regards,
Janos

[zed]

N.C, Thanks.

I searched for XFS, it's not a XFS. The toos i have would have picked it up (e.g X-Ways).

What would you suggest in order to repair the file system if i'm not sure what it is to begin with?

Also - i have seen NAS boxes with customised versions of Linux before. They take it and modify it a little bit.

See this review of this unit from Tom's hardware, the reviewer think's it's a revised version of reiserfs but did not manage to work it out:
http://www.tomshardware.co.uk/review-ds ... 214-6.html

"One somewhat unusual item I noticed while exploring the DS-101 flash image was the use of the Reiser filesystem. I had not previously seen this filesystem used in a consumer NAS device, so decided to do some additional exploration. I took the IDE drive out of the DS-101 and hooked it to my Desktop Linux system so that I could explore the filesystem. My first attempt to simply mount one of the partitions failed, with an error indicating that the partition was not in Reiser format!

Next, I did a simple ASCII dump of the first section of the partition to see if I was mistaken about the filesystem used. This is where I saw something curious. A standard Linux filesystem will have an ASCII signature present to tell the operating system what kind of filesystem is present. For Reiser, this will normally be "ReIsEr2Fs", but on the DS-101 initialized disk, I saw an "SyNoRs2Fs". Reading between the lines, this indicated to me that perhaps this was a "Synology Reiser2 Filesystem." Had Synology created a custom Reiser2 Filesystem? Or maybe they had just put in a custom signature.

To test this theory (don't try this at home kids!) I bypassed the filesystem by writing directly to the raw hard drive and overwrote the signature with the standard one. After I did this, I was able to mount the filesystem without error and I could see the top-level directories on the disk. But when I tried to examine any of the files, I would get an error indicating that the file didn't exist. This told me that it really was a modified Reiser filesystem, and not just a change in signature. For the time being this was as far as I was willing to explore, so I put the original filesystem signature back and re-assembled the DS-101."

[ccc]

Hi Zed

Take a look at the first line of the picture in your attachement...at the end of line it's something like that "ySoNsRF2".....try to read the second letter first then the first letter, after that the fourth letter and than the third...etc...what u get?...SyNoRs2F

Exactly the same case like in your example...

So......

Rgds

[zed]

ccc, i noticed that but that does not help me much in recovering the data. I have tried Stellar Pheonix for Linux (supporting Reiser), UFS Explorer (supports Reiser), X-Ways (supports Reiser) and some other methods. So far - i can't even see any files/folders as none of these programs support this file system.

Any ideas?

[hddguy]

This does use EXT3 filesystem, and it is supported with UFS Explorer (http://www.ufsexplorer.com/inf_nas.php)

I have never recieved this specific unit so cant offer much more help than this sorry.


Good luck