
- Why Regular Data Recovery Tools Can’t Restore Files from RAID
- Key Information About the NAS QNAP VS-8148U-RP Pro
- How to Remove Hard Disks from Your NAS and Connect Them to a PC
Why Regular Data Recovery Tools Can’t Restore Files from RAID
Conventional hard drives store user data by writing it sequentially across the disk surface, which means an entire file is typically located on a single drive. In contrast, when data is written to a RAID array, each file is split into multiple fragments. These fragments are then distributed and written in sequence across all the drives in the array. Depending on the configuration, fragment sizes can range from 2 KB to 2 MB, so every file is physically stored across several disks at once.
This approach significantly increases read and write performance — after all, writing two halves of a 1 GB file to two drives simultaneously is much faster than writing the full 1 GB to a single disk. However, this same mechanism makes file recovery far more complex.
Different RAID levels use different methods to distribute and protect data. On top of that, manufacturers like QNAP often add their own proprietary structures and variations. As a result, data can be written to disks in many different formats, and each requires a specific approach during recovery.
How can regular data verification or checksum processes help maintain data integrity on NAS QNAP VS-8148U-RP Pro devices?
Regular data verification or checksum processes can help maintain data integrity on NAS QNAP VS-8148U-RP Pro devices in the following ways:
- Detecting Data Corruption: Data verification processes involve comparing the checksums of files or data blocks with their expected values. If the checksums do not match, it indicates that the data has been corrupted. Regular verification helps identify corrupted data early on, allowing for prompt action to restore or replace the affected files.
- Preventing Silent Data Corruption: Silent data corruption refers to errors that occur during data storage or transmission without being detected by the system. By regularly running checksum processes, you can identify silent data corruption and take corrective measures before it leads to significant data loss or system failures.
- Ensuring Data Integrity during Transfer: When transferring data to or from the NAS device, checksum processes can verify the integrity of the transferred data. By comparing the checksums before and after the transfer, you can ensure that the data has been successfully and accurately transferred without any corruption or modification.
- Early Detection of Hardware Issues: Regular data verification can also help identify potential hardware issues within the NAS device. If checksum mismatches occur frequently or consistently, it may indicate problems with the storage media, memory, or other components. Identifying these issues early can help prevent data loss and allow for timely repairs or replacements.
- Maintaining Data Consistency: By regularly verifying the integrity of data stored on the NAS device, you can ensure that it remains consistent over time. This is particularly important in environments where multiple users or applications access and modify the data. Regular verification helps identify any inconsistencies or discrepancies that may arise due to accidental or unauthorized modifications.
Overall, regular data verification or checksum processes provide an additional layer of protection against data corruption, silent errors, and hardware issues. By incorporating these processes into your data management practices, you can enhance the reliability and integrity of your data on QNAP VS-8148U-RP Pro devices.
How to Remove Hard Disks from Your NAS and Connect Them to a PC
Although the NAS VS-8148U-RP Pro can be accessed over the network, you still need to remove its hard disks and connect them directly to a Windows PC. Only then can the recovery software properly scan and analyze the drives. Follow these steps:
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Power off the NAS and disconnect it from the power source.
WARNING! Before removing any drives, carefully read the device manual. Improper actions may damage both the NAS enclosure and the hard disks in the RAID array.
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Remove the hard disks one by one, gently sliding each drive out of its slot. Remember that hard disks are highly sensitive: any impact or drop can cause serious physical damage.
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Label each hard disk according to its position inside the NAS. The order of the drives is crucial for correct RAID reconstruction.
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Connect the drives to your computer. In this video, we explain which ports you can use to connect hard disks and what to do if your PC does not have enough free connectors.
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Step-by-Step Data Recovery with Hetman RAID Recovery

This program restores data from damaged RAID arrays and is fully compatible with QNAP VS-8148U-RP Pro. Each hard disk in the array contains technical metadata describing how files were written. When launched, Hetman RAID Recovery analyzes this metadata, automatically reconstructs the damaged array, and provides access to its contents. After that, you can browse the recovered disk and save your files. The program can also restore files that were accidentally deleted from the network drive.
How to recover data from a QNAP
VS-8148U-RP Pro has 8 HDD slots, and it supports the following array types:
- RAID 50;
- RAID 60;
- RAID 6;
- RAID 5;
- RAID 10;
- RAID 0;
- RAID 1;
- JBOD;
NAS supports:
- ZFS;
- EXT4;
- EXT3;
- exFAT;
- FAT32 (External Disk Only);
- NTFS (External Disk Only);
- HFS+ (External Disk Read Only);
How to Safely Recover Data from Disk Images
This utility allows you to create a complete copy of a disk and work with the disk image instead of the physical drive. This approach helps protect your data from:
- Overwriting during the recovery process;
- Additional data loss caused by bad sectors;
- User errors.
To create a disk image, follow these steps:
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Ensure you have enough free space to store the image. Its size will typically match the size of the original disk.
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In the main window, select the target disk and choose Tools - Save Disk. You can also select multiple disks if needed.
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When the Image Creation Wizard opens, select whether you want to save the entire disk or only a specific region. Adjust the settings and click Next.

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Choose the directory where the image will be saved. You may select any available disk connected to your PC or upload the image via FTP.

Where Are the User’s Files Actually Stored?
The QNAP VS-8148U-RP Pro network-attached storage keeps QTS (QuTS hero) operating system files on a separate RAID 1 (mirrored) array. Usually, all NAS systems create several volumes on every hard disk, and the first of them takes up to 2 Gb of space. This is where operating system files are stored. Other volumes are united into a RAID array where user’s data is written.
RAID Recovery Software: Detailed Comparison
| Product | Operating system | RAID controller support | Supported file systems | Virtual RAID controller support | Data recovery from damaged RAID | File preview |
|---|---|---|---|---|---|---|
| Hetman RAID Recovery | Windows, Linux, MacOS | Yes, over 100 controllers | FAT, exFAT, NTFS, ReFS, APFS, HFS+, Ext4, Ext3, Ext2, ReiserFS, Btrfs, VMFS, Hikvision, XFS, UFS, ZFS | Yes | Yes | Yes |
| DiskInternals RAID Recovery | Windows | Yes, over 10 controllers | FAT, NTFS, Ext2/3/4, HFS+ | No | Yes | Yes |
| R-Studio | Windows, Mac, Linux | Yes, over 20 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
| UFS Explorer RAID Recovery | Windows, Mac, Linux | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
| EaseUS Data Recovery | Windows | Yes, over 20 controllers | FAT, NTFS, Ext2/3/4, HFS+ | No | Yes | Yes |
| ReclaiMe Free RAID Recovery | Windows | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |


To make a backup for your QNAP VS-8148U-RP Pro NAS, you can follow these steps:
It is recommended to periodically check the backup status, update the backup settings, and test the restore process to ensure the backup's reliability.