- Why Regular Data Recovery Tools Can’t Restore Files from RAID
- Key Information About the NAS Digiever DS-16320-RM 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 Digiever 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 a NAS Digiever DS-16320-RM Pro+ device's caching policy impact data loss risks?
The caching policy of a NAS (Network Attached Storage) device such as the Digiever DS-16320-RM Pro+ can impact data loss risks in the following ways:
- Write-back caching: This caching policy allows data to be written directly to the cache memory before being written to the actual storage disks. While it improves write performance, it also increases the risk of data loss in case of power outages or system failures before the data is written to the disks. If the cache is not properly flushed, any data in the cache may be lost.
- Write-through caching: This caching policy writes data simultaneously to both the cache memory and the storage disks. It reduces the risk of data loss as data is immediately written to the disks. However, it may slightly impact write performance compared to write-back caching.
- No caching: Disabling caching eliminates the risk of data loss due to cache-related issues. However, it may negatively impact overall performance, especially for write-intensive workloads.
It's important to note that NAS devices often have additional features like battery backup units (BBUs) or uninterruptible power supplies (UPS) to mitigate the risks associated with power failures. These features help ensure that any data in the cache is safely written to the disks before a power outage occurs.
Ultimately, the choice of caching policy should be based on the specific requirements of the NAS usage scenario, balancing performance needs with data loss risks. It's advisable to consult the NAS device's documentation or seek expert advice to determine the most suitable caching policy for your specific needs.
How to Remove Hard Disks from Your NAS and Connect Them to a PC
Although the NAS DS-16320-RM 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 Digiever DS-16320-RM 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 Digiever
DS-16320-RM Pro+ has 16 HDD slots, and it supports the following array types:
- RAID 0;
- RAID 1;
- RAID 5;
- RAID 6;
- RAID 50;
- RAID 60;
- 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 Digiever DS-16320-RM Pro+ 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 |
Yes, it is possible to recover data from a NAS Digiever DS-16320-RM Pro+ device that has been affected by a controller card failure or interface problem. However, data recovery in such cases can be complex and may require professional assistance.
Here are a few steps you can take to attempt data recovery:
Note that attempting data recovery on your own without proper knowledge or tools may further damage the device or result in data loss. It is recommended to consult professionals for the best chance of successful recovery.