Repair Volumes Or Disk Groups; Change Raid Type - Synology DiskStation DS216j Quick Installation Manual

RAID Type HDD #
RAID 1 2-4
≧ 3
RAID 5
≧ 4
RAID 5+Spare
≧ 4
RAID 6
≧ 4
RAID 10
(even
number)
Create Disk Groups
As stated above, creating Disk Groups provides more flexibility when managing storage spaces. Disk Groups can
be created within the volume creation setup wizard, or you can go to
Create.

Repair Volumes or Disk Groups

The repair function is available for RAID 1, RAID 10, RAID 5, RAID 5+Spare, RAID 6, and SHR volumes or Disk
Groups. Depending on your RAID types, when one of the hard drives in the volume or Disk Group fails, it will be
in the degraded mode. You can repair the volume or Disk Group by replacing the crashed disk(s) to keep the
data on the volume or Disk Group protected. For more detailed instructions, please see

Change RAID Type

The RAID types of existing volumes and Disk Groups can be changed without losing existing data, allowing you
to easily and economically manage storage capacity. For example, you can create a RAID 1 volume on your
Synology NAS, and later change to RAID 5 if you install more hard disks.
The sections below provide basic information regarding changing RAID types. For more detailed instructions,
please see DSM Help.
Supported RAID Types
RAID types can be changed as follows.
RAID Type
Basic
RAID 1
RAID 5
Add mirror disk to RAID 1
SHR-1
27 Chapter 5: Manage Storage Space
Allowed
Failed HDD #
The system will write identical data to each hard
(HDD #) - 1 drive at the same time, so data integrity is
protected when at least one disk is normal.
This configuration includes a backup option. It
uses parity mode to store redundant data on
1
space equal to the size of one disk for later data
recovery.
A RAID 5+Spare storage space requires at least
four drives, one of which will act as a hot spare
2
drive to rebuild the failed drive of the volume
automatically.
RAID 6 provides extra data protection. It uses
parity mode to store redundant data on space
2
equal to the size of two disks for later data
recovery.
1 HDD within RAID 10 has the performance of RAID 0 and
each RAID 1 data protection level of RAID 1. RAID 10
group / Half of combines two hard drives into a RAID 1 group,
the total HDD and combines all the groups with RAID 0.
RAID 1, RAID 5, RAID 5+Spare
RAID 5, RAID 5+Spare
RAID 5+Spare, RAID 6
RAID 1
SHR-2
Synology NAS User's Guide
Description
Storage Manager > Disk Group
DSM
Can be changed to...
Based on DSM 6.1
Capacity
Smallest HDD
size
(HDD # – 1) x
(Smallest HDD
size)
(HDD # – 2) x
(Smallest HDD
size)
(HDD # – 2) x
(Smallest HDD
size)
(HDD # / 2) x
(Smallest HDD
size)
and click
Help.