- Why Regular Data Recovery Tools Can’t Restore Files from RAID
- Key Information About the NAS WD My Cloud PR2100
- 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 WD 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 the number of drives in a NAS WD My Cloud PR2100 device's RAID array impact data recovery and potential loss?
The number of drives in a RAID array in a NAS (Network Attached Storage) device like the WD My Cloud PR2100 can have an impact on data recovery and potential loss in the following ways:
- Data Redundancy: RAID arrays provide data redundancy by distributing data across multiple drives. The most common RAID levels used in NAS devices are RAID 1 (mirroring) and RAID 5 (striping with parity). In RAID 1, data is mirrored on two drives, while in RAID 5, data is striped across multiple drives with parity information. The more drives in the array, the higher the level of redundancy, which can help protect against data loss in the event of a drive failure.
- Increased Fault Tolerance: With more drives in the array, the NAS device can withstand multiple drive failures without losing data. For example, in a RAID 5 array with four drives, one drive can fail, and the data can still be accessed and recovered from the remaining drives. However, if another drive fails before the failed drive is replaced and rebuilt, data loss can occur. Having more drives in the array reduces the risk of data loss during the rebuilding process.
- Rebuilding Time: When a drive fails in a RAID array, the data from the failed drive needs to be rebuilt onto a replacement drive. During this process, the remaining drives in the array are under increased stress, which can increase the likelihood of another drive failure. With a larger number of drives in the array, the rebuilding process can take longer, increasing the exposure to potential data loss.
- Cost: Adding more drives to a RAID array increases the overall cost of the NAS device. However, the added cost can be justified by the increased data redundancy and fault tolerance provided by a larger array.
In summary, having more drives in a NAS device's RAID array can improve data redundancy, fault tolerance, and protection against drive failures. However, it can also increase the time required for rebuilding and the overall cost of the device.
How to Remove Hard Disks from Your NAS and Connect Them to a PC
Although the NAS My Cloud PR2100 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 WD My Cloud PR2100. 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.
My Cloud PR2100 has 2 HDD slots, and it supports the following array types:
- RAID 0;
- RAID 1;
- JBOD;
NAS supports:
- Ext2;
- Ext3;
- Ext4;
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 WD My Cloud PR2100 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, there are several software solutions available for data recovery from WD My Cloud PR2100 devices with S.M.A.R.T. errors. Some of the popular options include:
It's important to note that data recovery from NAS devices with S.M.A.R.T. errors can be challenging, and there is no guarantee of 100% success. It's recommended to consult with a professional data recovery service if the data is critical or valuable.