[Urgent] Replace Crashed HDD in NAS

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640
Hi guys,

I need some urgent advice.

I have a Synology NAS with 5 HDD's inside (Approx. 12 TB space), my 2nd HDD crashed today and volume 1 has failed. I don't have any sort of RAID backup option, just a automatic scheduled external HDD backup of the most important files that is always connected to the NAS.

At the moment i can seem to still access the files however, i can't edit, delete them or anything.

Now my question is, the NAS is saying to take HDD 2 out.

So, if i remove this HDD, will it cause problems with me accessing the files on the volume?
Will it kill off the whole volume?
or is it safe to remove the HDD and then replace it.


Which goes on to my next question, if i buy an exact same HDD as the one thats crashed can i make a one to one replicate of the crashed disk? or is it beyond that now?

Basically, what should i do? Im really worried, as i use my NAS daily and need an immediate solution.

Thank you.

 
Most volumes on a Synology Device will use Synology Hybrid RAID by default. That will protect you against a single disk failure. And in that case, replacing the failed disk with an identical one should allow you to rebuild the array and carry on without data loss.

However: if that were the case Volume 1 should still be available now, it might be marked as degraded, or have warnings, but should still be accessible and should not have failed.

If, when you oroginally configured volume 1, you specifically chose an option without redundancy, then unfortunately a failed disk will result in data loss. In that case, your only option is to replace the disk, rebuild a new, blank volume (preferably with redundancy this time) and restore data from your backup.
 

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640


I just checked the drives are of different sizes:
Disk 1: 2 TB
Disk 2 [failed]: 2 TB
Disk 3: 3 TB
Disk 4: 3 TB
Disk 5: 4 TB

So i need to replace the 2 TB drive with another 2 TB? or can i replace it with a larger 4 TB drive?
 

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640



Checking the summary of my volume this is what it shows:

Volume 1 - Crashed
RAID Type: JBOD (without data protection)

Unable to use this volume . The data in the volume maybe crashed. Please try to backup the data before removing the volume.

File System: ext4
Status: Crashed
Capacity: 12.51 TB
Used: 10.10 TB
Available: 2.41 TB

Volume 1 is still accessible and i even tried playing some videos from it and they worked. So does that mean it will work if i just replace the disk? and can it be a larger disk then the one already inside? or does it have to be the exact same size?

thanks
 
Oh no, you used JBOD? That's bad news I'm afraid. No redundency.

Seeing as you can access the volume *sort of*, try to copy whatever files you can off it. Depending on how the drives were written to, you may be able to get some files if no part of the file was written to the failed disk.

Once you've got what you can, do try a power cycle, there's a small chance the drive might come back up again for a while (in which case don't trust it, just your window to get the data off and replace the drive before it dies for good).

Once you've salvaged what you can, replace the drive, rebuild a new (fresh) volume with redundency (!!) and copy back whatever you managed to save from backups and the salvage operation.
 

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640
Yes i seem to be able to access all files as read only, i can't seem to edit or move/delete anything with the failed disc still in there.

I don't really want to rebuild a new fresh volume, as its not possible for me to backup all my 10TB data, i have only 4 TB backed up on external HDD. I don't have space to backup all 10TB.

So i guess my only other option is to try clone the HDD? Can someone please help me with pointers on how to do this? In the meantime i will try to order a new 2TB HDD to replace the failed one. Will make sure its exactly the same. All the HDD's are WD brand. Im really annoyed though as this one didn't seem to last over 4 years :(


 

TyrOd

Honorable
Aug 16, 2013
527
0
11,160


This is by far the safest solution.
 

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640


OK thank you, I've ordered the 2 TB Western Digital replacement drive. Ill put both of these in my pc tomorrow, any recommendations to trying to clone the drive? cause I've never attempted this before.

My other question, because I've selected the volume being JBOD without protection since the beginning, is there no way to change this now without having to start from scratch?

Thanks
 
I usually use the command line tools built into linux...

sudo dd conv=sync,noerror bs=8M if=/dev/sdX of=/dev/sdY

Where X is the input drive and Y is the output drive.

Not easy to change, plus you'd probably lose a bunch of capacity - RAID likes all the drives to be the same size. I'd probably look at picking up a pile of 4TB ones, move the data to them, pull the old drives, format them, move the data again, then build an array with the new drives and shove it back.
 

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640
Is there any recommended free software to use on windows rather then command line for the cloning?

Also in the meantime while the disk is crashed, is it still safe for the rest of the disks/volume if i leave the NAS on and continue to read data only from it?

 

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640


Thanks so much for your help @Someone Somewhere and all the others too!

One other thing say tomorrow when the new HDD arrives, i place it in the NAS where the failed one was. What will happen in this instance? Will it continue to function as normal will it have problems etc...?
 

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640
I checked on the WD site and the HDD still seems to be in warranty. Ive filed a RMA, and cancelled my new order from amazon earlier. For the RMA, it says they will post a new HDD first and then i can post the old broken one back within 30 days.

Does anyone know how long these usually take to arrive?

In the meantime, I've ordered another 4 TB external HDD to backup my remaining important stuff onto. Hopefully once i do that, i can think of a way to create a proper RAID NAS with my existing HDD's, it would be amazing if others can offer any suggestions on how i can achieve this!

Ive already backed up the NAS configuration file .dss, so hopefully that will make the restoration easier?! But again i have no idea what that will help bring back? Will it bring back all my NAS settings including any packages i installed on the NAS, user profiles, shared drive names etc...?
 
IMHO the best freeware cloning tool is ddrescue. It is specifically designed for cloning HDDs that have bad sectors. You can run it from a Ubuntu Live CD.

See http://www.tomshardware.com/forum/299286-32-need-flexible-sector-copy-software-failing

A SMART report would help us to determine the physical state of your drive. You could CrystalDiskInfo or smartmontools for this purpose.

There are other tricks that can be done at the firmware level to improve your chances of data recovery, but they require some level of comfort with the DOS command line.
 

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640
@fzabkar, thank you for the recommendations, as soon as i receive my replacement drive from WD i will give these methods a go. The drive was shipped on the 19th so should be here very soon. In the meantime, I've left the failed drive inside the NAS and bought a 4th external HD, I'm backing up all the remaining data on to that. Which is taking some time.

By the way i ran a SMART test scan on the bad drive from within the NAS, it fails at 90%, which to me means that only 10% of the drive is faulty with bad sectors?! Hopefully this might be able to be repaired?

 

Killer Nads

Honorable
Apr 30, 2013
68
0
10,640
Hi once again guys,

OK i received my replacement HDD from WD. I also took out the crashed hdd from my NAS now, and noticed that the whole volume disappears from my NAS once i do that, however as soon as i put it back in it all comes back with a Danger message saying that its crashed.

Anyhow, i put both the crashed HDD and new one inside my PC, i installed Acronis True Image WD Edition software and right now I'm trying to clone the failed HDD to the new one. I already know that the failed HDD has some bad sectors inside it (SMART scan was only able to reach 90% before giving error).

Now during the clone i received a message saying that the cloning has encountered a bad sector on the source, what would i like to do, try again, ignore or cancel.

I obviously clicked on ignore all.

Now my question to you guys is how will this affect my cloned drive once its complete? Theres still 5 hours to go. If it just ignores the bad sectors will the cloned drive still be ok? Im obviously looking to put the cloned drive back into my NAS and hope that i can access my old Volume again, at least for a while until i come up with a more permanent solution.

Is this a good idea? Any chance of it working? or because I'm ignoring the bad sectors in the clone once i put it back into the NAS it won't recognise it as being the same as the old HDD that failed?

Thanks
 

FireWire2

Distinguished
Killer Nads

Since you are able to read!
BACK UP your data NOW with ANY external USB

It may take long time and you may lost a little bit of data due to 2nd HDD failed.

That is the SAFEST and BEST option you have.
Once the data backup
Redo the NAS with redundant RAID like RAID5, do not use SPAN anymore
There is NO hope to recover your set up...

BTW: I hate these companies screw up all the terminologies and confuse users
JBOD is Just A Bunch of Drive - it is a multiple drives mode indivdually
When you combine indiscriminate HDD size, it CALLS "BIG/SPAN/LARGE/Concatenation" not JBoD