QNAP Systems Ts 253 User Guide

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Configuring Spare Drives 
 
 
 
With this function, a spare drive can be added to or removed from a RAID 1, RAID, 5, RAID 6, or 
RAID 10 configuration. Unlike a global spare drive, the drive in this case will be dedicated to the RAID 
group. Follow these steps to configure a spare drive: 
1. Go to Storage Manager > STORAGE > Storage Space.  
2. Double click a storage pool to bring up the Storage Pool Management page. 
3. Select a RAID group and click Manage > Configure Spare Drive.    
4....

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To disable a bitmap,  
1. Go to Storage Manager > STORAGE > Storage Space.  
2. Double click a storage pool to bring up the Storage Pool Management page. 
3. Select a RAID group and click Manage > Disable Bitmap (only available after a bitmap has 
been enabled) and then OK. 
 
Note: Bitmap support is only available for RAID 1, RAID 5, RAID 6 and RAID 10. 
  
Recovering Failed RAID Disk Volumes 
 
This can recover failed RAID disk volumes from the Inactive status to a normal state (RAID 1, RAID 
5,...

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Data Scrubbing 
 
Data Scrubbing scans the sectors of RAID groups and automatically attempts to repair failed sectors 
to maintain the consistency of the file system. This function is only supported by    RAID 5 and RAID 6 
and cannot be performed on a RAID Group that is in degraded mode. We recommend setting up a 
scheduled task for this function to avoid losing any critical data in the event of disk failure. Note that 
read/write performance may be affected during data scrubbing.  

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Cache Acceleration 
 
Based on SSD technology, the Cache Acceleration feature is designed to boost access performance of 
the NAS. On this page, you can both monitor SSD performance and manage cache acceleration for 
your NAS. This chapter covers the following topics: 
Feature Requirements 
Creating SSD Volumes 
Removing SSD Volumes 
Expanding SSD Volumes 
Configuring Volumes for SSD Cache 
 
Feature Requirements 
 
SSD drives must be installed to enable this function and this...

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4. Choose the SSD Cache Mode: 
o Accelerate random I/O: Only small random I/O will be stored in SSD cache. This mode is 
recommended for virtualization and database applications. Also, select the bypass block size 
under this mode (block sizes that are larger than the specified one will not be cached).  
o Accelerate sequential I/O:    All I/O will be stored in SSD cache. This mode is recommended for 
video streaming or large file access operations.  
5. Select (or deselect) from the list to enable...

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3. The settings will be applied to the chosen volume. 
 
Note:  
For larger block, sequential I/O operations such as video streaming, the hit rate is 
lower, and by default, they are not recorded in the cache space. If you need to record 
such operations, please cancel this setting, but please remember that after this setting 
is cancelled, more cache space and computing resources will be consumed for such 
operations. 
Not all applications can benefit from a SSD cache. Please make sure that...

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Snapshot 
 
Snapshot Vault stores snapshots created remotely from remote NAS via Snapshot Replica in Backup 
Station. It also lets you manage and restore remote snapshots.  
 
 
In this chapter, the following topics are covered: 
Snapshot 
o Taking a Snapshot 
o Managing Snapshots with Snapshot Manager    
o Snapshot Global Settings 
o Managing Previous Versions in Windows 
Snapshot Vault 
o Filtering Snapshots 
o Displaying Snapshot Content 
o Removing Snapshots 
o Cloning Snapshots...

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o * x51 series models only support up to 256 snapshots instead of 1024. The HS-251 
does not support snapshots. 
 
Snapshot  
 
Taking a Snapshot 
After a reserved space is set, you can proceed to take snapshots. To create a snapshot, follow 
these steps: 
1. Go to Storage Manager > STORAGE > Snapshot.  
2. Switch between Volume or LUN depending on your needs, select a volume/LUN, and 
click Take a Snapshot.  
3. Specify the snapshot name, duration to retain the snapshot and snapshot type (the...

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Revert snapshots 
Select a snapshot and click Revert to restore the snapshot to its 
original path. 
Warning: The volume reverted to the selected snapshot will be in the previous state when 
the snapshot was taken. 
 
Clone snapshots to new 
volumes or LUNs 
1.  Select a snapshot and click Clone. 
2.  Type an alias for the new volume, and select the folders to 
share after cloning. 
Note: You can map cloned LUN snapshots to iSCSI targets. 
 
Delete snapshots Select a snapshot and click Delete to...

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Reservation section. 
 
Managing Previous Versions in Windows 
Starting with QTS 4.2.1, snapshots can be used with the Previous Versions feature in 
Windows, allowing you to instantly revert to a previous version of a file in the event of an 
accident (e.g. file deletion, corruption, or accidental changes.) 
  
To use this feature, follow these steps: 
1. In Windows, connect to a shared folder on the NAS (the shared folder must be located in 
a storage pool where snapshots can be taken.) 
2. Take...