Rebuild goes wrong

Everything looked nominal. This case is actually kind of unexpected example of routine operation going belly up, the NAS owner ends up looking for recovery options after RAID 5 crash

Recently our quite old NAS Iomega Storcenter 200rl with a RAID 5 out of 4x500GB, reported a harddisk failure and our administration replaced one of the disks that was marked. Then the Storecenter told that it was synchronizing the data. After synchronization the NAS told that 100% of storage capacity is free and so it tell until now… I am interessted in options to revocer the data.

Certainly does not look like something was done wrong; if the NAS have sensed the rebuild cannot be completed, it would have had refused to even start the process. Certainly, with a wrong disk replaced, the rebuild does not happen. In this case, however, the rebuild was completed with no reported anomaly – something else went wrong.

With something unknown going wrong, it is difficult to predict if the case is recoverable. One can give our Home NAS Recovery a spin, but there is no guarantee of success. Cases when rebuild goes wrong for no apparent reason are always dicey.

 

 

Network Recycle Bin and undelete

This specific question is about IX4-300d, but it applies to virtually any NAS out there.

The question is about some Recycle Bin equivalent for a NAS.

As in most NAS (if not all) when a file is deleted from a share in IX4-300d it disaappear “completely” from the drive. No chances to recover it from a Recycle bin. I read in a post that UNDELETE by Diskeeper might be a solution creating a “virtual” recycle bin. I decided to try it and downloaded a trail version of the program. But it did not recognized the drive/shares in the NAS. Does anyone has any experience with UNDELETE in NAS?

First of all, some NAS vendors provide an equivalent of the Windows Recycle Bin. QNAP, for example, calls this feature Network Recycle Bin. It keeps files retrievable as best practically possible (subject to age and free space constraints).

Whatever delete protection mechanisms, they must be implemented and run on the NAS side, because it is the NAS filesystem that owns the files and performs deletions. Any Windows-based installable recycle bin software only works with locally attached disks.

After the files are deleted with no Recycle Bin in place, there is still a chance – our Home NAS Recovery can help (with varying success depending on how long since the deletion).

Lost RAID5 on Thecus

Trying to rebuild lost Raid5 on Thecus

I have lost a raid 5 in a 4200PRO and now I am desparatly trying to revive the Raidset.

What happened: The Raid5 over 4x 2TB WDGreen Disks degraded and I accidently marked the wrong disk as spare (this was definately my mistake, failure before always happend on drive #3, this time it was #4…), next boot the raid was gone.

[tried to fix the problem using Linux commands but to no avail].

Has anybody any experience how to get further than this?

Yes, but the success depends on what exactly was done during troubleshooting. Unless the rebuild was forced on a wrong disk order, Home NAS Recovery is a definite answer to the question.

Prior Planning Prevents Poor Performance

People seem overly concerned about how to do the recovery should their NAS go down. These two cases (first, second) concern Thecus NASes.

If I create RAID 1 and the N3200Pro hw fails beyond repair (for whatever reason), can I take out one of the HDDs out and read the files on it in a Linux or Windows PC? I am only interested in reading the data once at that stage, rebuilding the RAID is a non-issue …

and

Assuming that I have a Thecus N2310. Assuming that I have a disk that *was* part of a RAID1 but the other disk is missing. What steps do I need to do with the disk and the N2310 to rebuild the RAID array and get the data off please?

I was describing this at some length in another post, but just for a short repeat, if you are worried about recovering data should the NAS dies, why not have a backup for it? The data may get damaged for reasons other than a total and utter NAS hardware failure. Lightning strike, software issue, or a number of other reasons will damage both sides of the RAID1 at the same time. RAID does not replace a backup.

Prevention is good

Every now and then, people plan and go to great lengths figuring how to do data recovery before the actual data loss occurs.

What type of file system does the ix2 use with hard drives? For safety, I’d like to know how to recover data from the drives if the ix2 fails. I do not like the idea of relying on some hidden proprietary format that requires the ix2 to be able to retrieve my data in case of failure.

Anyone know how to read the disk formatted by the ix2 from a PC running any operating system?

There is no hidden proprietary format actually. Lenovo/Iomega uses run-of-the-mill Linux software and filesystems. However, the great confusion ensues little further in the discussion, mixing up filesystems with RAIDs, RAIDs with backup, single-disk RAID1 with a single partition, you name it.

Well, let’s spell it out

  1. Any NAS would use this-or-that form of RAID.
    1. Even if you have a single disk in a multi-bay NAS, it will have a single-disk RAID, most likely RAID1, to avoid changing data format if you add a second drive.
    2. Furthermore, if you have a single-bay NAS, it is still likely to have a single-disk RAID, to achieve compatibility across the entire model lineup (and specifically the ability to move the drive to the multi-bay model).
  2. Most modern NASes use one of the standard Linux filesystems, XFS, EXT3, EXT4, or BTRFS.
  3. If there is no damage to the data on disks, or the damage is minor, and assuming skilled operator, a properly configured Linux PC will read the data if all disks are connected at the same time.

But, the most important question here is: if one plans for data recovery before the actual loss, why do not have a backup instead of recovery?

 

ix4-200d unsuccessful drive replacement

Someone had to go to a data recovery center when his Iomega StorCenter ix4-200d has a rebuild failure

I have a StoreCenter ix4-200d [with 4 disks in RAID10] that had a drive failure. I … replaced the damaged drive. On restart the screen on the StoreCenter said “Drive 1 requires overwrite confirmation“, but when I go into the dashboard, there is no message for confirmation, and it has not lost all storage folders and shows 0 data stored.

… and that’s actually the end of story. Further troubleshooting attempts in earnest require the drives to be out of the NAS, no matter if you use Linux and mdadm, or Windows and data recovery software. However, as it often happens, some tinkering with mdadm was attempted, unfortunately with no effect, but fortunately without any ill side effects. The story ends happily, although not cheap

 

Yes i found a solution… I did send my storecentre to a recovery service centre and they managed to restore the data 100%…the total cost for this recovery €3000 !!!

That may seem tad high for a 4 disks in RAID10, as the drives were still readable and probably did not both require extensive mechanical work. The corresponding Home NAS Recovery license would have been little short of $200, plus a cost of four replacement drives.

IX4 falling apart

This documents a typical sequence of multiple drives failing in a RAID5, this time in Iomega ix4-200d.

I’ve received an automatic email from the dashboard saying

Data protection is being reconstructed. Data is available during this operation, however performance may be degraded.

After that, the NAS started ‘Data recovery procedure’ [and then came another message]

Drive number 1 encountered a recoverable error.

[and] NAS started recovery procedure from the scratch. Even though that mentioned drive has failed, everything worked fine untill yesterday [when] new message … said

Storage failed and some data loss may have occurred. Multiple drives may have either failed or been removed from your storage system. Visit the Dashboard on the management interface for details.

Is there any way to recover at least some data if it is NAS that failed?

Depending on the condition of the disks, Home NAS Recovery may or may not be able to extract data from it.

Maybe there was a spare involved, as data protected is being reconstructed in a RAID5 can only refer to a rebuild of the array. The rebuild happens either when a defective disk was replaced or when a hot spare kicks in after one of the active array disks fails. There is another variation to that tune, not really obvious, which is a transient failure causing one of the disks to drop out of the array momentarily, then report back online and be accepted back in the array.

Anyhow, while rebuild is in progress, it turns out the second drive in the array is unreadable. This halts the rebuild. The error is at first deemed recoverable, and the rebuild is retried. However, the error recovery is not successful and the second disk (#1) drops offline. With two drives offline, the data is no longer accessible.

For our data recovery software, the logical reconstruction is not a problem given that the disks are still readable enough. This may be a problem though. In worst case, the disks need to be cloned to a blank new disks, and clones then used for recovery. The NAS will not accept the clones because it already has recorded the disks as “failed”, and cloning the entire disk content also clones the “failed” marks for respective disks.

The case for the Linux way

This case looks like it can be solved with Linux fairly easy

I own an Iomega storcenter ix2-200, with several shares… Shares show up as empty, on my pc as well as on the webinterface. … However, the webinterface also indicates that there 1.2 TB of data (the blue indicator), which should be the real size. Therefore, I assume the data is still present, but something has been messed up. Does anyone know / have suggestions how I can regain access to my data?

Shares not containing data is obviously bad. However, the case as a whole does not look that bad, because the volume is still indicating 1.2 TB in use, so the data is still there somewhere. Most likely, attaching the disk set to a Linux PC will allow to copy the data away. This should not be difficult given it is only two disks. Then, some Linux chmod may be in order to override any possible access restrictions, and the data should be there for the asking.

SHR on two identical disks

The set of questions from here, while SHR-specific, applies to NETGEARs X-RAID as well.

I have a DS213j set up as Synology Hybrid RAID (SHR) with 2 2TB disks. What happens if the DS213j fails? Are the disks just mirrors so that I can connect either to a PC and see it as an external drive and recover the data? If not would it be better to change to RAID 1? What are the advantages of SHR over RAID 1?

SHR means Synology Hybrid RAID. The advantage of SHR is that SHR can better utilize capacity of mixed size disks, and SHR supports some weird disk upgrades which are normally done by deleting and rebuilding the traditional array.

However, if we are talking two identical disks and no plans to upgrade, SHR is in effect the same as RAID1, so there is really no choosing one or the other.

My Book World single disk

The most basic question about a WD NAS – How to recover data from a failed My Book World edition?

I have a 1TB My Book World … Logged in yesterday, just to reboot it (always figure its healthy to reboot devices/servers every few months). …  it says ‘drive not recognized’, and failed to mount drive. Updated firmware on unit, still the same… … taken HDD out the enclosure, and plugged it into my PC (Windows7).

Windows can see 5 partitions on the drive, as not NTFS/FAT32, i know it will format and lose the data the moment i try and add the drive….Any ideas on what software i can use to extract my data off the drive ???

Sure. Use Home NAS Recovery. This is not even expensive for a single disk.

For the record, it is not a good idea to reflash firmware on a bricked NAS. If something goes bad to worse, the newly flashed firmware may initiate some kind of initialization as the NAS may think the disks are blank. Side effects of initialization are never good.