QNAP Systems Ts 253 User Guide

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Volume: Volumes are storage spaces on your NAS. A volume is formatted by the file system to 
store shared folders and files. There are three types of volumes: thick, thin and static. Thick/thin 
volumes must be created in a storage pool, and a storage pool can contain multiple thick/thin 
volumes. A thick/thin volume can be resized to a greater capacity if there is available space in the 
storage pool. Static volumes, on the other hand, are created from a RAID group instead of a 
storage pool. A static volume can be expanded by adding new RAID groups into it or by adding 
new disks to an existing RAID group. More information on volumes can be found here. 
iSCSI LUN: iSCSI LUNs are logical volumes mapped to iSCSI targets. There are two types of 
LUNs: block-based and file-based. Block-based LUNs are usually preferred to File-based LUNs. The 
difference between block-based LUN and file-based LUN can be found here. 
Shared folder: Shared folders are created in volumes and are used to store and share files with 
users or groups that have access privileges. 
 
For more information on Storage Manager, please refer to the links below: 
Creating new storage pools.    
Creating new volumes.    
Creating new shared folders. 
Creating iSCSI LUNs. 
 
Advanced Storage Architecture 
Qtier - Auto-tiering storage management architecture 
 
 
Qtier storage pool: Qtier is an automated-tiering storage solution that consists of different types 
of disks to form a multiple-drive volume that during low-load times or based on your schedule: 
o Moves frequently used data onto high-performance disks (ie. SSDs) for high-availability or high 
I/O cache throughput. 
o Moves less frequently used data onto low-cost, high-capacity disks (ie. SATA drives) for better 
cost efficiency. 
There are three speed tiers of disks: 
o Ultra-High speed tier: Ultra-high speed tier is a RAID group that consists of SSD for hot data.  
						

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o High speed tier: High speed tier is a RAID group that consists of SAS disks for the data that is 
between hot data and cold data.  
o Capacity tier: Capacity tier is a RAID group that consists of SATA disks for cold data. 
Cache Acceleration: The Cache Acceleration feature is designed to boost access performance of 
the NAS by the use of SSD(s). More information on cache acceleration can be found here. 
 
Click here for more information on setting up Qtier. 
 
Disaster-recovery storage management architecture 
 
 
Snapshot: Take a snapshot to record the state of a volume/LUN. After snapshots are taken, they 
can be used to restore the volume/LUN’s state to the time the snapshot was taken. Users may 
also choose to only restore particular folders/files in the volume from the Snapshot. 
Snapshot Replica: The Snapshot Replica allows you to replicate the volume/LUNs between 
different remote servers using snapshot technology, which provides a flexible and efficient backup 
service for IT professionals. 
Snapshot Vault: Snapshot Vault stores snapshots sent from remote NAS via Snapshot Replica. 
Snapshot Vault also lets you manage and restore remote snapshots. 
 
Click here for more information on creating replication jobs. 
  
This architecture supports four distinct types of volumes adapted by QNAP over the years, and each 
volume type supports different storage features: 
 
  
						

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Features Legacy 
Volume 
Static 
Volume 
QTS 4.1 Storage 
Pool Flexible 
Volume 
QTS 4.2 Storage 
Pool Flexible 
Volume 
Performance level High High Medium Medium 
Online RAID 
migration 
● ● ● ● 
Online RAID 
expansion 
● ● ● ● 
File-based LUN ● ● ● ● 
Block-based LUN   ● ● 
Thin provisioning   ● ● 
SSD cache  ● ● ● 
JBOD RAID 
expansion  ● ● ● 
JBOD expansion 
roaming  ● ● ● 
Snapshot    ● 
Snapshot Replica    ● 
Snapshot Vault    ● 
 
For specific setup of the Storage Manager, please refer to the following links: 
Dashboard 
Storage  
						

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iSCSI 
Virtual Disk 
 
Note:  
It is strongly recommended that each JBOD has its own storage pool.    Do not create storage 
pools that include hard drives outside the JBOD. Only add new disks to the JBOD (or replace the 
existing disks in the JBOD) when expanding the storage pool. Otherwise, data stored on the 
JBOD will become inaccessible when connected to a different NAS host. 
To migrate storage pools from a previous firmware version to QTS 4.2, please check the 
migration tutorial: 
https://www.qnap.com/i/au/trade_teach/con_show.php?op=showone&cid=139  
						

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Dashboard 
 
The Storage Manager dashboard provides an overview for IT administrators to easily monitor and 
manage storage allocations.  
 
 
Overview 
 
There are three sections on the page: Disk, Volume/LUN and Storage Pool. They are described below: 
Disk: The physical hard disk drives and their associated storage hosts (including both the NAS and 
its connected expansion enclosures) are shown in this section. Click the hard disk drive icon to 
bring up the Disk Health window. For details on the Disk Health window, please refer to the Disks 
chapter. 
Volume/LUN: All available logical volumes, their capacity and type (Volume, LUN and Unused) are 
listed in this section. For details on volumes and LUN, please refer to the Volumes chapter. 
Storage Pool: This section provides a space usage overview on the storage pool created on the 
NAS. You can check the space distribution on the pie chart for each storage pool (including the 
size of reserved system space, thick volume and free space) and its subscription. Subscription is 
the ratio between claimed space and available space in the storage pool. If a user creates a 
thin-provisioned volume with 10TB claimed space, while the available space is only 1TB, the 
Subscription value in the Overview page will be 10:1, meaning that the thin-provisioned space 
is oversubscribed and users must note that the available space in storage pool is too low. You can 
also click on the down arrow next to the storage pool to switch between storage pools. For details 
on storage pools, please refer to the Storage Pools chapter. 
  
						

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Utilization 
 
This page is designed for users to monitor storage utilization of their NAS. With volume and storage 
pool usage information presented on this page, users can manage their storage system more 
effectively and spot potential issues based on trends over a period of time (from the last hour to the 
last year.) 
 
Select to view the storage usage rate of a particular volume or storage pool and specify the period. 
Click Clear Record to reset the utilization graph.      
 
Note: Utilization only applies to certain NAS models. To check for applicable models, please refer to 
the product comparison table on the QNAP website.  
						

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Storage 
 
Manage volumes, storage pools, hard disk drives, snapshots, encrypt and decrypt file systems, and 
configure cache acceleration with Storage Manager.        
 
 
For details on the features, refer to the following links: 
Disks/JBOD 
Storage Space 
Cache Acceleration 
Snapshot 
Qtier (Auto Tiering) 
 
Note: Some of the features listed above are applicable to certain models. Please check for 
applicable models first as you review descriptions of the features.   
						

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Disks/VJBOD 
 
This page is designed for users to monitor and manage hard disk drives installed on the NAS and its 
connected expansion units (both expansion enclosures and VJBOD (also known as Virtual JBOD)). 
Users can quickly isolate and identify hard drives for relevant maintenance tasks. 
 
 
In this chapter, the following topics are covered: 
Disks  
o Managing NAS Hosts 
o Managing Disks 
o HDD S.M.A.R.T. Information 
o Disk Health Global Settings 
Expansion Enclosures 
o Managing Physical Expansion Enclosures 
o Recovering Physical Expansion Enclosures 
o Managing Virtual Expansion Enclosures (VJBOD) 
Introducing VJBODs 
Creating VJBODs with new iSCSI LUN (using Create Virtual JBOD’s Disk Wizard) 
Creating VJBODs with existing iSCSI LUN (using Create Virtual JBOD’s Disk Wizard) 
Using VJBODs 
Managing and Monitoring VJBODs 
Detaching and Reconnecting VJBODs 
Data Roaming 
Automatic Reconnection 
  
						

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Disks 
 
Note: Hot-plugging is not supported for M.2, PCIe, and mSATA drives. 
 
Managing NAS Hosts 
Click a NAS under NAS Host in the system component panel to check its general information. Refer to 
the following table for actions available to manage a NAS host: 
Action Description 
Enclosure 
Info 
Click this button to check details of an enclosure, including the model, serial 
number, firmware version, BUS type, BIOS version, CPU temperature, system 
temperature, power status, system fan speed and power fan speed. 
Locate 
(under 
Action) 
Click this button and the chassis LEDs of the selected NAS host will blink for easy 
identification. 
RAID Group Click this button and select a RAID group to check its details, including capacity, 
RAID group name, RAID type and disk member. 
 
Note: You can click NAS Host in the system component panel and click Action > Port 
Table to check the port speeds. 
 
Managing Disks 
Click + beside the NAS host in the system component panel and select a disk to check its general 
information. The legend shown under the system component panel is provided to indicate the types of 
hard disk drives: 
Cache: A disk drive configured as cache. 
Data: A disk drive that contains data. 
Free: An empty disk drive that does not have any data on it. 
Spare: A disk drive configured as spare drive for a RAID group. 
Error: A disk drive detected with errors (could be bad sectors or I/O errors) and it is 
recommended that this disk drive is to be replaced immediately. 
Warning: A disk drive is approaching failure. 
 
Refer to the following table for actions available to manage a disk: 
 
 
 
  
						

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Action Description 
Disk Info Click this button to check details of a disk, including the model, model number, 
serial number, capacity, firmware version, ATA version and ATA standard. 
Disk Health Click this button to check disk S.M.A.R.T information. More details about 
S.M.A.R.T information will be provided in the next table. 
Scan Now 
(under 
Action) 
Click this button to scan the disk for bad blocks. If bad blocks are found, the 
number of bad blocks will be displayed in the Status field. Check the bad block 
sectors by clicking on the bad blocks message so long as the disk is not busy.  
 
You can also use this function if a drive is in an error state. In this case, if no 
bad blocks found after a complete scan, the error state of drive will be changed 
back to normal. 
Locate (under 
Action) 
Click this button to locate drives using LED lights for easy identification of 
physical hard drives. 
Set as 
Enclosure 
Spare (under 
Action) 
Click this button to set the chosen hard disk drive as an enclosure spare drive in 
RAID 1, RAID 5, RAID 6, or RAID 10. In case a spare drive is shared by multiple 
RAID groups, that spare drive will be used to replace the first failed drive across 
all RAID groups. Please note that the capacity of the enclosure spare drive must 
be equal to or larger than that of the member drive in a RAID group and this 
option is only available for an empty disks. Note that an enclosure spare can 
only be used within an enclosure. 
Disable Spare 
(under 
Action) 
Click this button to cancel the chosen hard disk drive as an enclosure spare 
drive. 
New Volume 
(under 
Action) 
Click this button to create a new volume. For details, please refer to the chapter 
on Volumes. 
RAID Group Click this button and select a RAID group and check its details, including 
capacity, RAID group name, RAID type and disk member. 
View Mode 
(located above 
the system 
component 
panel) 
Switch to list view using the list view icon on top-left of the page. In the list 
view, you can show or filter for disks. Set the filter from the drop down list to 
only show hard disks based on the device (enclosure or NAS they belong to), 
model, type (HDD or SSD), BUS type, capacity, used type (data, free, error, 
spare, cache, or none) and status. Click Refresh to refresh the list. 
You can also perform sequential read and IOPS read tests (under Performance