Synology DS412+ – Repairing a Degraded Volume

Volume 1 is degraded due to a failed hard disk (Disk 2 is missing)

The Synology DS412+ started beeping on the one of the nights when I just got back from work. At first I thought my neighbour’s appliances/alarm clock was beeping and disregarded it. When I walked past the Synology DS412+, I realised one of the disk’s status LED was not lit. Is the disk down?

I started to worry for the data on the Synology Hybrid RAID Volume. Quickly fired up my browser, accessed the DSM and checked the Storage Manager. I was right, disk 2 has failed and no more information was provided.

So how do one recover from degraded RAID volume on the Synology DS412+ on Synology Hybrid RAID (SHR)? It turns out to be 3 simple steps:

  1. Turning off the warning beep
  2. Replacing the failed hard disk drive (hot-swappable)
  3. Repairing the RAID volume


Turning off the warning beep

31st March 2017 The beep control can now be found under Control Panel > Hardware & Power.

I guess this step is really optional if you do not find the every 2 seconds beep irritating. For me, I prefer to turn it off after knowing what went wrong with the volume. Turn off the warning beep by:

  1. Navigating to the DSM page (your Synology NAS’s IP address) using a desktop web browser. The mobile DSM does not give you an option to turn off the beep
  2. Login to the DiskStation Manager (DSM)
    You should be shown the DSM desktop 
  3. From the “Start” menu, launch Storage Manager
    Storage Manager should launch 
  4. In the Storage Manager, select the Volume tab
  5. In the Volume tab, click on the “Beep off” button
    The warning beep should stop and the “Beep off” button will be grey-ed off

With the warning beep off, it is time to replace the faulty hard drive.
Replacing the failed/faulty hard disk drive

You should always replace the failed/faulty hard disk drive with one of similar specifications. It can be larger in size but not smaller as it will affect the size of the total RAID volume. To find out the available size of a RAID volume, use the Synology RAID calculator.

For the replacement hard disk, you can either:

  • Get a brand new one and switch place with the faulty disk; or
  • Extract the fault disk, send it for warranty replacement and wait the replacement

Do note that if you are going for option 2 of waiting for replacement, do note that you do not enjoy data protection. If any of the remaining disks fail, you will lose your data.

The physical replacement of the hard drive is quite straight forward, you can eject the drive when the Synology NAS is still up and running (if it is hot-swappable) or you can do it when the Synology NAS is powered down.

With the new hard drive inserted, the system logs should reflect a newly inserted hard disk. Similarly, the “HDD Management” tab in “Storage Manager” should reflect the newly added hard disk. Once the new hard disk has been reflected, proceed to the next section.


Repairing the volume

This is the most time consuming part of the entire process as the DSM will be rebuilding the newly inserted hard disk. It all depends on the size of the volume, the bigger it is, the longer the wait.

  1. Login to the DiskStation Manager (DSM)
  2. From the “Start” menu, launch Storage Manager
    Storage Manager should launch
  3. In the Storage Manager, select the Volume tab

    The Volume tab in Storage Manager
  4. In the Volume tab, click on the Manage button
    A Volume Manager Wizard should launch

    Repairing the volume after replacing Disk 2 with a new one
  5. In the Volume Manager, select the Repair option and click on the Next button
  6. Select the newly inserted hard disk and proceed by clicking the Next button
    A warning prompt highlighting that “all the data in the new disk will be erase” should be prompted

    Choosing the disk to be rebuilt based on the volume information on the remaining disks
  7. Acknowledge the warning prompt by clicking the Ok button

    Ensuring that you have selected the correct disk and you know what you are doing
  8. Once you have confirm the settings for the repair, click on the Apply button

    Confirmation of settings. Repairing the volume with the replaced Disk 2.
  9. If done correctly, you should see that Volume 1 is back to 4 disks and the status of the volume should be reflected as “Repairing”.

    After the root and swap volume has been restored, the DS412+ proceeds with the parity consistency check.
  10. Congratulations! You have kick started the repair process. In the mean time, the volume will still be accessible, albeit a little slower due to the repair process.



The Synology DS412+ successfully rebuilt the new disk with the necessary information. The RAID volume is up and running with data protection of 1 disk fault-tolerant again!

This is very important as I had use other NAS which had problems rebuilding the RAID volume. Some even formatted the data drive instead of the new disk, worsening the problem further.

I am glad that the DiskStation Manager knows what it is doing and the repair process is easy without needing the end user know all those Linux commands. This is how a good product should be!


Treat shadowandy!

If these step-by-step guides have been very helpful to you and saved you a lot of time, please consider treating shadowandy to a cup of Starbucks.  

14 thoughts on “Synology DS412+ – Repairing a Degraded Volume

  • August 21, 2012 at 10:16 pm


    from your previous articles, I guess that the failing disk was the WD red, was it ?
    I just bought a DS412+ to replace my old DS110j and I’m still wondering about which drive I’ll buy, my samsung HD204UI just crash randomly after 2 years of good service.

    Would you be able to make some R&W test while downloading from bittorrent, in my case the DS110j was insufficient as viewing a simple 720p video was almost impossible while downloading 2-3MB/s torrents, the 128MB memory might not have been large enough to handle correctly the torrents download plus the data streaming for video playback.

    Best regards in Singapore and nice articles BTW.

  • September 11, 2012 at 9:40 pm


    Great article.

    I’m using DS212+ and I had to replace my 1TB (7200rpm) WD Enterprise disk after 1.5 month of usage. The degraded status = “Disk not initialized”. I’ve run the repair process once disk was replaced and I could still work on my NAS while Volume was being repaired. Fantastic option! It took me 4 hours to repair 1TB and 98GB of data.


  • September 11, 2012 at 9:57 pm


    The Synology is amazing right? Totally worth the investment! At least I know mine is!

  • December 8, 2012 at 6:17 am


    One of my two HDD has a “system partition failure”. If I repair the volume without replacing the drive will it wipe all data? Is there a chance repairing will fix the issues with the HDD? It’s a WD Caviar Green 2TB and it’s only about 4 months old so I’m quite dissapointed that it has failed…



  • December 8, 2012 at 12:10 pm


    What is the RAID configuration for the drives?

  • February 24, 2014 at 6:41 pm

    Thanks for the great guide. One slight update – the “manage” button is now on the “Disk Group” tab not the Volume tab (I’m running DSM version 4.2)

  • February 25, 2014 at 7:39 pm

    Neal Harrington,

    Thanks for the heads up! I hope I won’t get to repair degraded volumes again!

  • April 28, 2014 at 1:15 am


    My first hard drive (out of 4 on a DS413j) crashed and is now being repaired (it will take around 20 more hours, I have 4x3Tb drives) but I have no access to any file. Do you think it is due to the fact that the 1st drive crashed? or because I had to flash the DSM.

    Thanks a lot and bravo for your article8

  • April 28, 2014 at 11:02 am


    What is the RAID you chose for your setup? By right you should still have access to your file just that it will be slightly slower. It might be good to check on the SMART status of your hard disk (the one that failed) to ensure that it is not faulty when it is back up.

  • May 9, 2014 at 11:00 am


    I cant able to connect after restart the server. HDD led not initiated in FS server. Please help me

  • July 17, 2014 at 9:00 am

    My NAS DS412+ just crash and the whole information of the company is on it… i don´t have any back ups and my head is on risk
    The second drive appear Not Initialized and the other two appear normal but i can´t see any file on it, if i repair the not initialized drive can i lose the information on the NAS?

  • July 19, 2014 at 9:45 pm

    Miguel Burciaga,

    The best advice from me will be contacting Synology support. I was hoping that you have setup RAID 5 or SHR as they pretty much protect you against single hard disk failure.

Comments are closed.