
- Why Regular Data Recovery Tools Can’t Restore Files from RAID
- Key Information About the NAS Buffalo TeraStation TS-RH4.0TGL/R5
- 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 Buffalo 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 Buffalo TeraStation TS-RH4.0TGL/R5 device's RAID array impact data recovery and potential loss?
The number of drives in a NAS Buffalo TeraStation TS-RH4.0TGL/R5 device's RAID array can have a significant impact on data recovery and potential loss.
- Redundancy: RAID arrays are designed to provide redundancy and fault tolerance. The more drives in the array, the higher the level of redundancy. In the case of the TS-RH4.0TGL/R5, it uses RAID 5 configuration, which requires a minimum of three drives. With three drives, the array can tolerate the failure of one drive without losing any data. If a fourth drive is added, it further improves redundancy and can tolerate the failure of two drives.
- Data Recovery: In the event of a drive failure, the NAS device can rebuild the data from the remaining drives using parity information. The larger the number of drives in the array, the longer the rebuild process will take. During this time, the array is in a vulnerable state, as another drive failure can result in data loss. So, having a larger number of drives increases the risk of data loss during the rebuild process.
- Potential Loss: If multiple drives fail simultaneously or within a short period, the data in the RAID array can be lost. In a RAID 5 configuration with three drives, the failure of two drives would result in complete data loss. Adding more drives to the array reduces the risk of simultaneous failures, but it does not eliminate it entirely.
It is important to note that RAID is not a substitute for regular backups. While RAID provides some level of protection against drive failures, it cannot protect against other forms of data loss such as accidental deletion, file corruption, or catastrophic events. Regular backups should be implemented to ensure data can be recovered in case of any unforeseen circumstances.
How to Remove Hard Disks from Your NAS and Connect Them to a PC
Although the NAS TeraStation TS-RH4.0TGL/R5 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:
-
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.
-
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.
-
Label each hard disk according to its position inside the NAS. The order of the drives is crucial for correct RAID reconstruction.
-
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.
Go to view
Step-by-Step Data Recovery with Hetman RAID Recovery

This program restores data from damaged RAID arrays and is fully compatible with Buffalo TeraStation TS-RH4.0TGL/R5. 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 Buffalo
TeraStation TS-RH4.0TGL/R5 has 4 HDD slots, and it supports the following array types:
- RAID 0;
- RAID 1;
- RAID 5;
- RAID 6;
- 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:
-
Ensure you have enough free space to store the image. Its size will typically match the size of the original disk.
-
In the main window, select the target disk and choose Tools - Save Disk. You can also select multiple disks if needed.
-
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.

-
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 Buffalo TeraStation TS-RH4.0TGL/R5 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 specific firmware updates and patches recommended for data recovery from NAS Buffalo TeraStation TS-RH4.0TGL/R5 devices. Buffalo periodically releases firmware updates to improve the functionality and performance of their devices, including data recovery features. It is recommended to regularly check for firmware updates on Buffalo's official website and install them to ensure that you have the latest version with the most up-to-date data recovery capabilities. Additionally, Buffalo may also release specific patches or updates to address any known issues or vulnerabilities that could affect data recovery on the TeraStation devices. It is important to stay updated with these patches to ensure the best possible data recovery experience.