Increase storage pool size

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Increase storage pool size

DS213J, DS918+
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I am running out of space and want to upgrade one of my HD but don’t see the option to “replace drive” per the synology directions. Is there another area I need to do this.

Also I have a 918+ in SHR1 running four 6TB drives. Will I get any increase in space with 1 HD or do I need to upgrade 2 at a time for increased capacity. Thanks


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There are certain requirements when replacing drive button/feature will appear:

Please also note the following:

  • The Replace Drive button will only appear when all the following criteria are met:
    • The storage pool is in one of the following RAID configurations: SHR, SHR-2, RAID 1, RAID 5, RAID 6, RAID 10, or RAID F1.
    • The storage pool is composed of at least two drives.
    • Your Synology NAS contains at least one unused drive.
  • A replacement drive can only replace a drive of the same type:
    • A SATA drive can only replace a SATA drive; a SAS drive can only replace a SAS drive.
    • A 4K native drive can only replace a 4K native drive; a non-4K native drive can only replace a non-4K native drive.
    • An HDD can only replace an HDD; an SSD can only replace an SSD.
  • Only one drive can be replaced at a time.

To replace a drive (when there are no unused drives or empty drive slots):​

If your Synology NAS does not contain any unused drives or there are no empty drive slots for installing replacement drives, you can perform the following steps instead. We provide an example of replacing the drives of an SHR storage pool in the steps below.

  1. Launch Storage Manager.
  2. Go to the Storage page and select the storage pool you want to expand its capacity.
  3. Check which existing drive is the smallest.
  4. Power off your Synology NAS. (Skip this step if your Synology NAS supports hot-swapping.)
  5. Remove the smallest of the member drives and install a new, larger drive.
    Note: To avoid harming yourself or damaging your Synology NAS, please follow the drive installation instructions found in the Hardware Installation Guide for your Synology product.
  6. Power on your Synology NAS.
  7. Launch Storage Manager again.
  8. Go to the HDD/SSD page to make sure the new drive is recognized.
  9. Go to the Storage page and select the storage pool. It should be in a Degradedstatus.
  10. Click
    and select Repair to repair the storage pool.
  11. Select the replacement drive to add to the storage pool and then follow the wizard to finish.
  12. Repeat the above process until all desired drives have been replaced with larger ones.
Thanks. I missed that part. And also found out that I will need 2 drives to increase usable space. So would I upgrade 1 drive. Then turn off again and install second drive?
Correct. With your current array configuration, you will have to replace one drive at a time. Let it rebuild, then continue with the following one. Pulling multiple drives will crash your array instead of just "degrading" it.

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