QNAP Systems Ts 253 User Guide

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LUN Backup 
 
The NAS supports backing up iSCSI LUNs to different storage locations (Windows, Linux, or 
local shared folders), restoring the LUNs to the NAS, or creating a LUN snapshot and mapping 
it to an iSCSI target. 
 
In this chapter, these topics are covered: 
Backing up iSCSI LUNs 
Restoring iSCSI LUNs 
Creating iSCSI LUN Snapshots 
Managing LUN Backup/Restore/Snapshot by Command Line 
 
Note: This function or its content is only applicable on some models. To check for 
applicable models, please refer to the   product comparison table on the QNAP website. 
A minimum of 4 GB RAM is required to use snapshots. 
x51 series models only support up to 256 snapshots instead of 1024. The HS-251 does 
not support snapshots. 
 
Backing up iSCSI LUNs 
 
The entire LUN can be backed up as an image file and saved to a different location. The 
storage location can be a Windows share (SMB/CIFS), a Linux share (NFS), or a local folder 
on the NAS. 
 
Before backing up an iSCSI LUN, make sure at least one iSCSI LUN has been created on the 
NAS. To create iSCSI targets and LUN, go to Storage Manager > LUN Backup. 
1. Click Create a job. 
2. Select Back up an iSCSI LUN and click Next. 
3. Select the source LUN for backup. If an online LUN is selected, the NAS will automatically 
create a point-in-time snapshot for the LUN. 
4. Specify the destination where the LUN will be backed up to. The NAS supports LUN 
backup to a Linux share (NFS), a Windows share (CIFS/SMB), and a local folder on the 
NAS. Click Test to test the connection to the specified path. Then click Next. 
5. Enter a name of the backup LUN image or use the one generated by the NAS. Select the 
subfolder where the image file will be stored. Select to use compression or not and click 
Next. (Use Compression: When this option is enabled, more CPU resources of the NAS 
will be used but the size of the backup LUN can be reduced. The backup time may vary 
depending on the size of the iSCSI LUN.)  
						

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6. Specify the backup schedule, choose the backup period (Now, Hourly, Daily, Weekly, or 
Monthly) and click Next.  
7. The settings will be shown. Enter a name for the job or use the one generated by the 
NAS. Click Next. 
8. Click Finish to exit. 
9. The backup job is shown on the list. 
 
Refer to the table below for actions (the Action button) available to manage the backup 
jobs. 
Action Description 
Edit Edit the job settings. 
Delete Delete the job. 
Start Start the job immediately. 
Stop Stop the running job. 
View Logs View the job status and logs. 
 
Restoring iSCSI LUNs 
 
A LUN image can be restored to the NAS. Users can choose to overwrite the original LUN or 
create a new one by renaming the LUN. To restore an iSCSI LUN to the NAS, follow these 
steps:  
1. Go to Storage Manager > LUN Backup. Click Create a job. 
2. Select Restore an iSCSI LUN and click Next. 
3. Specify the protocol, IP address/host name, and folder/path of the restore source. Click 
Test to test the connection. Then click Next. 
4. Browse and select the LUN image file and click Next. 
5. Select the destination and click Next.  
6. The settings will be shown. Enter a name for the job or use the one generated by the 
NAS. Click Next. 
7. Click Finish to exit. 
 
The restore job will be executed immediately.  
 
Refer to the table below for actions (the Action button) available to manage restore jobs. 
 
 
  
						

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Action Description 
Edit Edit the job settings. 
Delete Delete the job. 
Start Start the job immediately. 
Stop Stop the running job. 
View Logs View the job status and logs. 
 
Note: For Step 5 above:  
Overwrite existing LUN: Restore the iSCSI LUN and overwrite the existing LUN on the 
NAS. All the data on the original LUN will be overwritten. 
Create a new LUN: Restore the iSCSI LUN to the NAS as a new LUN. Enter the name 
and select the location of the new LUN. Make sure you have created at least one LUN 
on the NAS before editing the default LUN policy. 
 
Creating iSCSI LUN Snapshots 
 
A read-only LUN snapshot can be created and mounted to an iSCSI target on the NAS for 
data access from other hosts or LUN backup. The contents of the LUN snapshot will remain 
the same regardless of the changes made to the original LUN. Before creating an iSCSI LUN 
snapshot, make sure at least one iSCSI LUN and one iSCSI target has been created on the 
NAS.  
To create an iSCSI LUN snapshot, follow these steps: 
1. Go to Storage Manager > LUN Backup. Click Create a job. 
2. Select Create a LUN Snapshot and click Next. 
3. Select an iSCSI LUN on the NAS. Only one snapshot can be created for each iSCSI LUN. 
Click Next. 
4. Enter a name for the LUN snapshot or use the one generated by the NAS. Select an 
iSCSI target where the LUN snapshot is mapped to. Click Next. The LUN snapshot must 
be mapped to another iSCSI target different from the original one. 
5. Specify the snapshot schedule and the snapshot duration and click Next. The snapshot 
will be automatically removed when the snapshot duration is reached. 
6. The settings will be shown. Enter a name for the job or use the one generated by the 
NAS. Click Next. 
7. Click Finish to exit. 
8. The snapshot will be created immediately. The status and duration will be shown on the 
list.  
						

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9. Go to Storage Manager > iSCSI Storage, and the snapshot LUN will be shown in the 
iSCSI Target List. Use iSCSI initiator software to connect to the iSCSI target and access 
the point-in-time data on the snapshot LUN.  
 
Note: The source LUN and snapshot LUN cannot be mounted on the same NAS or certain 
operating systems such as Windows 7 and Windows 2008 R2. In this case, mount the LUN 
snapshot to a different NAS or server. 
 
Managing LUN Backup/Restore/Snapshot by Command Line 
 
QNAP NAS users can execute or stop the iSCSI LUN backup, restore, or snapshot jobs on the 
NAS by command line. Follow the instructions below to use this feature: 
1. First make sure the iSCSI LUN backup, restore, or snapshot jobs have been created on 
the NAS in Storage Manager > LUN Backup. 
2. Connect to the NAS by an SSH utility such as Putty.  
3. Login the NAS as an administrator. 
4. Input the command lunbackup. The command usage description will be shown. 
5. Use the lunbackup command to start or stop an iSCSI LUN backup, restore, or snapshot 
job on the NAS. 
 
Note: The above procedure should only be carried out by administrators who are familiar 
with command line interfaces.  
						

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Virtual Disk 
 
You can use this function to add iSCSI targets of other NAS or storage servers to the NAS as virtual 
disks for storage capacity expansion. The NAS supports up to 8 virtual disks. 
 
Supported file systems: 
Format: Ext3, Ext4, FAT, NTFS, and HFS+. 
Mount: Ext3, Ext4, FAT, NTFS, and HFS+. 
 
Note: 
The NAS supports a virtual disk with a maximum size of 16TB. 
When a virtual disk (iSCSI target) is disconnected, the virtual disk will disappear from the 
interface and the NAS will try to connect to the target in 2 minutes. If the target cannot be 
connected to after 2 minutes, the status of the virtual disk will become Disconnected. 
Each virtual disk drive will be recognized as a single logical volume by the local system. 
This function is only applicable to some models. To check for applicable models, please refer to 
the   product comparison table  on the QNAP website. 
 
To add a virtual disk to the NAS, follow the steps below:  
1. Make sure an iSCSI target has been created. Go to Storage Manager > Remote Disk and click 
Add Virtual Disk.  
2. Enter the target server IP and port number (default: 3260). Click Get Remote Disk and select a 
target from the target list. If authentication is required, enter the username and the password. 
Select the options Data Digest and/or Header Digest (optional). These are the parameters for 
which the iSCSI initiator is verified when it attempts to connect to the iSCSI target. Then, click 
Next.  
3. Enter a name for the virtual disk. If the target is mapped with multiple LUNs, select a LUN from 
the list. Make sure that only this NAS can connect to the LUN. The NAS supports mounting EXT3, 
EXT4, FAT32, NTFS, HFS+ file systems. If the file system of the LUN is Unknown, select Format 
virtual disk now and choose the file system. You can format the virtual disk as EXT3, EXT4, FAT 
32, NTFS, or HFS+. By selecting Format virtual disk now, the data on the LUN will be cleared. 
Then, click Next.  
4. Click Finish.  
5. The storage capacity of the NAS is expanded by the virtual disk. Users can go to Privilege 
Settings > Share Folders to create new shared folders on the virtual disk. 
 
Refer to the table below for actions (the Action button) available to manage virtual disks:   
						

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Action Description 
Edit Click this button to edit a virtual disk name or the authentication 
information of an iSCSI target. 
Connect Click this button to connect to an iSCSI target. 
Disconnect Click this button to disconnect an iSCSI target. 
Format Click this button to format a virtual disk as EXT3, EXT 4, FAT 32, NTFS, or 
HFS+ file system.  
Delete Click this button to delete a virtual disk or an iSCSI target. 
 
External Device 
You can use an external device as a virtual disk. Check the External Device chapter for details.   
						

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Security 
 
Go to Control Panel > System > Security to configure relevant security settings for your 
NAS.  
 
 
Security Level 
 
Specify the IP address or network domain from which connections to the NAS are allowed or 
denied. When the connection of a host server is denied, all the protocols of that server are 
not allowed to connect to the NAS. After changing the settings, click Apply to save the 
changes. Network services will be restarted and current connections to the NAS will be 
terminated. 
 
Network Access Protection 
 
Network access protection enhances system security and prevents unwanted intrusion. You 
can block an IP address for a certain period of time or indefinitely if the IP address fails to 
login to the NAS using a particular connection method (e.g. SSH, Telnet, HTTPS, FTP, SAMBA, 
or AFP). 
 
Certificate & Private Key  
 
Secure Socket Layer (SSL) is a protocol for encrypted communication between web servers 
and browsers for secure data transfer. You can upload an SSL certificate issued by trusted 
providers. After uploading an SSL certificate, users can connect to the administration  
						

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interface of the NAS by SSL and there will not be any alert or error message. The NAS only 
supports X.509 certificates and private keys. 
Replace Certificate: Upload a new certificate from a trusted provider, create a self-signed 
certificate, or get one from the open certificate authority “Let’s Encrypt”. 
Download Certificate: Download the secure certificate which is currently in use. 
Download Private Key: Download the private key which is currently in use. 
Restore Default Certificate & Private Key: Restores the secure certificate and private key 
to system default. The secure certificate and private key in use will be overwritten. 
Note: This option is only available after the default certificate has been replaced. 
 
Password Policy 
 
Password policy allows the administrator to set the minimum password strength of user 
passwords and to force users to change their passwords periodically. 
 
Password Strength 
 
Specify the password rules. After applying the setting, the NAS will automatically check the 
validity of the password. 
A new password must contain characters from at least three of the following types of 
characters: lowercase letters, uppercase letters, digits, and special characters. 
No character in the new password may be repeated more than three consecutive times. 
The new password must be different than the username and must not be the username 
reversed. 
 
Force Password Change 
 
The administrator may force users to change their passwords periodically by setting the 
number of days before a password expires. There is also an option to email users a week in 
advance of their password expiring.  
						

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Hardware 
 
Go to Control Panel > System Settings > Hardware to configure the NAS hardware 
functions. 
 
 
In this chapter, the following topics are covered: 
General Settings (General) 
Audio Alert 
Smart Fan 
 
General Settings (General) 
 
Enable configuration reset switch: When this is enabled, you can press the reset 
button for 3 seconds to reset the administrator password and the system settings to 
default (NAS data will be retained) or 10 seconds for advanced system reset.    
o Basic system reset: You will hear a beep after pressing and holding the reset button. 
The following settings will be reset to default:  
System administration password: admin. 
TCP/IP configuration: Obtain IP address settings automatically via DHCP. 
TCP/IP configuration: Disables Jumbo Frames. 
TCP/IP configuration: If port trunking is enabled, the port trunking mode will be 
reset to Active Backup (Failover).  
						

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System port: 8080 (system service port.) 
Security level: Low (Allows all connections.) 
LCD panel password: (blank); this feature is only for NAS models with LCD panels. 
VLAN will be disabled. 
Service binding: All NAS services will be run on all available network interfaces. 
o Advanced system reset: You will hear two beeps after continuously pressing the 
reset button. The NAS will reset all system settings to default (similar to the system 
reset in Administration > Restore to Factory Default) except all the NAS data will 
be reserved. Settings such as users, user groups, and shared folders will be cleared. 
To retrieve old data after an advanced system reset, create the same shared folders 
on the NAS and the data will be accessible again. 
Enable hard disk standby mode: This option allows the NAS drives to enter standby 
mode if there is no disk access within the specified period. Note that during standby 
mode, the system LED on the NAS will be off but the HDD status LED will remain steady. 
Enable light signal alert when the free size of SATA disk is less than the value: 
The status LED will flash red and green if this option is enabled and the free space of the 
SATA hard drive is less than the set value.  
Enable write cache (EXT4 only): If the NAS disk volume uses EXT4, enable this option 
for higher write performance. Note that an unexpected system shutdown may lead to 
data loss. It is recommended to disable this option if the NAS is set as shared storage in 
a virtualized or clustered environment. 
Enable warning alert for redundant power supply on the web-based interface: If 
two power supply units (PSU) are installed on the NAS and connected to the power 
sockets, both PSU will supply the power to the NAS (applied to 1U and 2U models.) Turn 
on the redundant power supply mode in System Settings > Hardware to receive 
warnings for the redundant power supply. The NAS will sound and record error messages 
in System Logs if the PSU is plugged out or does not respond correctly. If only one PSU 
is installed on the NAS, DO NOT enable this option. This function is disabled by default. 
Turn on LED light: If your NAS has a LED indicator (ex. TS-453mini), you can choose to 
turn on its LED indicator, set the LED brightness level and configure a schedule for the 
brightness setting. This function is only applicable on some models. 
 
Audio Alert 
 
You can configure the buzzer or speaker alarm for system operations and events. The 
following options are available: 
System operations: The system beeps or announces messages when system operations 
such as booting and firmware updates occur.  
System events: The system beeps or announces error or warning messages for system 
events.