- Why Regular Data Recovery Tools Can’t Restore Files from RAID
- Key Information About the NAS D-Link DNS-320
- 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 D-Link 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 hardware failure lead to data loss in NAS D-Link DNS-320 devices?
Hardware failure in NAS D-Link DNS-320 devices can lead to data loss in several ways:
- Disk failure: The most common hardware failure in NAS devices is the failure of hard drives. If one or both of the hard drives in the DNS-320 fail, it can result in data loss. The NAS device may not be able to access the data on the failed drive, and if the data is not backed up elsewhere, it can be permanently lost.
- Power supply failure: If the power supply unit (PSU) of the DNS-320 fails, it can cause the NAS device to shut down abruptly. This sudden power loss can lead to data corruption or loss if the device was in the middle of writing or reading data.
- Controller failure: The controller in the DNS-320 manages the communication between the hard drives and the rest of the system. If the controller fails, it can prevent the NAS device from accessing the data on the hard drives, resulting in data loss.
- Network interface failure: The NAS device relies on its network interface to connect to the network and allow users to access their data remotely. If the network interface fails, it can make the NAS device inaccessible, preventing users from accessing their data.
- Firmware or software corruption: Hardware failures can sometimes cause firmware or software corruption in the NAS device. This can result in the device becoming unresponsive or unable to access the data on the hard drives.
To mitigate the risk of data loss due to hardware failure, it is important to regularly back up the data on the NAS device to an external storage device or cloud storage. Additionally, using RAID (Redundant Array of Independent Disks) configurations such as RAID 1 can provide some level of data redundancy by mirroring the data across multiple hard drives.
How to Remove Hard Disks from Your NAS and Connect Them to a PC
Although the NAS DNS-320 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 D-Link DNS-320. 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 D-Link
DNS-320 has 2 HDD slots, and it supports the following array types:
- RAID 0;
- RAID 1;
- JBOD;
NAS supports:
- exFAT, VFAT, FAT 12 / 16 / 32;
- NTFS / ReFS;
- APFS / HFS+;
- Ext2 / 3 / 4 / ReiserFS / XFS / UFS / ZFS / Btrfs;
- VMFS / HikvisionFS;
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 D-Link DNS-320 network-attached storage keeps OS Linux 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 |
It is possible to recover data from a physically damaged NAS device, but the success of the recovery depends on the extent of the damage. If the power surge only affected the power supply or other internal components, it may be possible to repair or replace those parts and retrieve the data. However, if the damage is extensive, such as to the hard drives or other critical components, the recovery process may be more challenging or even impossible. It is recommended to contact a professional data recovery service for an assessment of the device and to determine the feasibility of data recovery in your specific case.