Disk

A physical device that stores and retrieves data.

QTS restricts which type of disk can be used for SSD cache and storage space (static volumes and storage pools). For details, see Disk Types.

RAID group

A group of one or more disks combined into one logical disk. RAID groups usually contain disks that are of the same type and capacity.

Data is distributed across the disks in a RAID group. Each RAID type offers a different combination of reliability, performance, and capacity.

For details, see RAID.

Storage pool

A pool of storage space consisting of one or more RAID groups.

Storage pools can aggregate RAID groups that consist of disks of different types and capacities. Storage pools enable easier storage space management and features such as snapshots.

Volume

A portion of storage space that is used to divide up and manage space on the NAS.

You can create volumes by dividing up storage pool space, or using the space of a RAID group. QTS offers three different volume types, with different combinations of performance and flexibility.

iSCSI LUN (logical unit number)

A portion of storage space that can be used by other NAS devices, servers and desktop computers using the iSCSI protocol.

QTS offers two LUN types.

• Block-based LUN: Created from a storage pool. It is similar to a volume, except that it has no file system and must be linked to an iSCSI host.

• File-based LUN: Created on a volume. It is similar to an ISO image file.

Shared folder

A folder that is used for storing and sharing files.

Shared folders are created on volumes. QTS automatically creates a set of default shared folders. You can create more shared folders and configure permissions for each.