Volume
You can use all the space of selected hard disks to create one volume, or create a volume on an existing Disk Group. Data protection in different levels may be provided according to the RAID type you choose when creating the volume. For RAID types supported by Synology RackStation, please refer to General.
To create a volume:
- Click the Create button.
- Choose a creation mode.
- Quick: This is the easiest way for general users to create a volume. The system will create a SHR volume for you to get the optimal balance of space and performance.
- Custom: This is for advanced users who want to choose their own RAID type when creating a volume.
- Follow the wizard to complete the process.
Note:
If you want to create a volume with a certain hard disk but it doesn't appear in the Volume Creation Wizard, please check the status of the hard disk in HDD Management tab.
To remove a volume:
- Select the volume you want to remove.
- Click the Remove button and follow the wizard to complete the process.
Note:
Data on the volume will be deleted after you remove the volume. Be careful when using this option.
To repair a volume:
When a volume is in Degraded status and the suggestion field in the Volume tab shows the link of Repair the system partition in blue, you can repair the volume simply by clicking the link. Then the volume status will be back to normal.
When the volume is in Degraded status but it is not due to system partition failure, you can repair it when the RAID type is one of the followings: SHR, RAID 1, RAID 5, RAID 5+Spare, RAID 6, and RAID 10. The data on the volume will be consistent after repairing. Please follow the steps below to repair your volume:
- Turn off your RackStation. You can skip this step if your model supports hot-swapping.
- Remove the failing hard disk as indicated in Disk Info of the page and replace it with a new one.
- Click Manage.
- Select Repair.
- Follow the wizard to complete the process.
Note:
- The size of the hard disk for replacement must be larger or equal to the size of the smallest disk in the volume.
- The status of the hard disk for replacement must be "Initialized" or "Not Initialized".
- To repair a volume created on a Disk Group, you have to repair the Disk Group to have the volume back to normal. The link in the suggestion field in the Volume tab will bring you to the Disk Group tab. Please follow the suggestion to repair the Disk Group. For more information, please refer to Disk Group.
Changing the RAID Type of Volumes
You can change the RAID type of a volume if there are available hard disks on your RackStation. Currently, the following types of RAID change are supported:
- Basic to RAID 1, RAID 5 or RAID 5+Spare
- RAID 1 to RAID 5 or RAID 5+Spare
- Add mirror disk to RAID 1
- RAID 5 to RAID 5+Spare or RAID 6
- RAID 5+Spare to RAID 6
Please follow the steps below to change the RAID type of your volume:
- Select the volume you want to change.
- Click Manage.
- Select Change RAID type.
- Follow the wizard to complete the process.
Note:
- You can only change the RAID type of a volume when it is in Normal status. Otherwise it will cause data loss. If the volume is in Degraded status, please repair it first.
- If you want to change the RAID type of a volume, enough number of hard disks for the new RAID type is required. The size of the selected hard disk must be larger than the smallest disk in the volume.
- The status of the added hard disk must be "Initialized" or "Not Initialized".
Expanding the Size of Volume
For multiple volumes on RAID, you can expand the volume size simply by clicking Edit button when selecting the volume. For SHR volume and a single volume on RAID, you can expand their size by replacing existing hard disks with ones of larger size or by adding hard disks.
Note:
- To expand a volume or Disk Group with 3 TB or larger disks, make sure your volume or Disk Group was created using DSM 3.0 or later.
Expanding Volumes by Replacing Existing Disks
You can expand a volume by replacing existing hard disks with ones of larger size in the following RAID types: SHR, RAID 1, RAID 5, RAID 5+Spare, and RAID 6.
RAID 5 and RAID 6
When replacing hard disks of RAID 5 or RAID 6 volumes or Disk Groups, the smallest hard disk should always be replaced first. The storage capacity of RAID 5 volumes is (number of hard disks – 1) x (smallest hard disk size), and RAID 6 is (number of hard disks – 2) x (smallest hard disk size). Therefore, the smallest hard disk should always be replaced first in order to maximize hard disk usage.
For example, if your RAID 5 volume contains three hard disks that are 4 TB, 3 TB, and 2 TB respectively, the available capacity of your volume will be 4 TB. If you replace the 4 TB or 3 TB disks, the capacity of the volume will not change. To increase the capacity of your volume, the 2 TB hard disk must be replaced first.
SHR (Synology Hybrid RAID)
When replacing hard disks belonging to SHR volumes or Disk Groups, please note the following:
- If the capacity of all member hard disks is equal, then you should replace at least two hard disks. Otherwise, the capacity of your volume will not expand. For example, if your SHR volume consists of three 3 TB hard disks, then you must replace at least two hard disks in order to expand volume capacity.
- If the capacity of member hard disks is different, then the new, replacement hard disks should be equal to or larger than the largest existing hard disk. In addition, you should replace smaller member hard disks first in order to optimize capacity usage. For example, if your SHR volume consists of three hard disks that are 4 TB, 3 TB, and 2 TB respectively, then your new, replacement hard disks should be at least 4 TB. In addition, you should replace the 3 TB or 2 TB hard disks.
To replace disks:
- Turn off your RackStation. You can skip this step if your model supports hot-swapping.
- Replace one hard disk with another of larger size.
- Turn on the RackStation and repair the volume.
- Repeat step 1 to 3 until all hard disks are replaced with ones of larger size.
- The system will expand the volume automatically.
Note:
- When replacing the spare disk of a RAID 5+Spare volume, the RAID type will be changed to RAID 5. After replacing the spare disk of a RAID 5+Spare volume, you need to click Manage and choose Change RAID type to change the RAID type back to RAID 5+Spare and choose the new spare disk as the larger one. Then you can expand the RAID 5+Spare volume.
- All services of Storage Manager will be temporarily stopped during the expansion process.
- You can only expand the hard disk when the volume is in Normal status; otherwise it will cause data loss. If the volume is in Degraded status, please repair the volume first.
Expanding Volumes by Adding Disks
For SHR, JBOD, RAID 5, RAID 5+Spare, and RAID 6, the storage capacity of volumes can be expanded by adding more hard disks if there are empty hard drive bays in your RackStation.
Minimum Hard Disk Size
Please see the guidelines below regarding the minimum size of new hard disks.
- For SHR: The capacity of the hard disk you wish to add must be equal to or larger than the largest hard disk in the volume or Disk Group. For example, if your volume is composed of three hard disks – 2 TB, 1.5 TB, and 1 TB respectively – then the capacity of the new hard disk must be at least 2 TB.
- For RAID 5, RAID 5+Spare, or RAID 6: The capacity of the hard disk you wish to add must be equal to or larger than the smallest hard disk in the volume or Disk Group. For example, if your volume is composed of three hard disks – 2 TB, 1.5 TB, and 1 TB respectively – then the capacity of the new hard disk must be at least 1 TB.
To add more hard disks:
- Select the volume you want to expand.
- Click Manage.
- Select the hard disks with which you want to expand the size of RAID.
- Follow the wizard to complete the process.
Note:
- The volume status must be Normal.
- For RAID 5, RAID 5+Spare and RAID 6 types of volume, the hard disk size must be larger than the smallest disk in the volume.
- The status of the selected hard disk must be "Initialized" or "Not Initialized".
Data Scrubbing
Data scrubbing is a data maintenance function that inspects volumes or Disk Groups and repairs any detected data inconsistencies. This function can be used with volumes or Disk Groups that implement SHR (comprised of three or more disks), RAID 5, or RAID 6.
We recommend regularly performing data scrubbing in order to maintain data consistency and avoid losing any critical data in the event of disk failure.
To perform data scrubbing:
- Select the volume or Disk Group on which to perform data scrubbing.
- Click Manage
- Select Data scrubbing.
Note:
- Data scrubbing can only be performed when the status of the volume or Disk Group is Normal.
- Please do not shut down the system before data scrubbing is completed. If the system is shut down before completion, data scrubbing must be restarted from the beginning.