
- Why Regular Data Recovery Tools Can’t Restore Files from RAID
- Key Information About the NAS QNAP TVS-872XU-RP
- 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 TVS-872XU-RP devices?
Regular data verification or checksum processes can help maintain data integrity on NAS QNAP TVS-872XU-RP devices in the following ways:
- Detecting Data Corruption: Regular data verification processes involve checking the integrity of the stored data by comparing it against a calculated checksum value. By periodically running data verification checks, any data corruption or errors can be detected. This ensures that the data stored on the NAS device remains intact and has not been altered or corrupted.
- Preventing Silent Data Corruption: Silent data corruption refers to the situation where data gets corrupted without any immediate indication or error message. Regular data verification processes can help identify such silent data corruption by comparing the stored data with the checksum value. If the checksum does not match, it indicates that the data has been corrupted, allowing for timely action to restore the data from backups or other measures.
- Early Detection of Hardware Issues: Data verification processes not only check the integrity of the stored data but also verify the health of the underlying hardware components. If errors are detected during the verification process, it may indicate potential hardware issues like faulty hard drives or memory modules. Identifying these issues early on can prevent further data corruption and allow for timely hardware maintenance or replacement.
- Ensuring Data Consistency: By regularly running data verification or checksum processes, data consistency can be ensured across different copies or backups of the data. If inconsistencies are detected, it indicates that one or more copies of the data have been corrupted or modified. This allows for taking corrective actions like restoring the data from a known good backup or identifying the cause of inconsistency and rectifying it.
- Maintaining Data Reliability: Data integrity is crucial for maintaining the reliability of the stored data. By regularly verifying the data using checksum processes, the NAS device can ensure that the data remains reliable and trustworthy. This is particularly important for critical data or sensitive information where any corruption or alteration can have significant consequences.
Overall, regular data verification or checksum processes on NAS QNAP TVS-872XU-RP devices can help in maintaining data integrity, preventing data corruption, detecting hardware issues, ensuring data consistency, and maintaining data reliability.
How to Remove Hard Disks from Your NAS and Connect Them to a PC
Although the NAS TVS-872XU-RP 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 TVS-872XU-RP. 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
TVS-872XU-RP 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 TVS-872XU-RP 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 |


If the disks of a QNAP TVS-872XU-RP NAS device have been reformatted, data recovery becomes more challenging but not impossible. Reformatting erases the file system metadata, making it difficult for the operating system to locate and access the data. However, the actual data might still be present on the disks until overwritten by new data.
To recover data from reformatted disks on a QNAP NAS device, you can try the following steps:
Remember, the success of data recovery depends on various factors, such as the extent of disk usage after reformatting and the effectiveness of the recovery software or service.