- Why can’t ordinary software tools restore files from RAID?
- How to take hard disks out of the NAS and connect them to a PC?
Why can’t ordinary software tools restore files from RAID?
Conventional hard disks keep user’s data by writing it to their surface in a consecutive way, and this is how an entire file is stored on a single hard disk. However, when data is written to a RAID system, a file is divided into several parts. Then these parts are written consecutively to all hard disks within such array. The size of such parts may range from 2 KB to 2 MB, so each file is stored on several hard disks at the same time.
Such approach helps to speed up read and write operations, and it is evident that saving two parts of a file having the size of 1 GB to two hard disks simultaneously is much faster than saving the same 1 GB of data to one hard disk. However, this peculiarity makes file recovery more complicated.
Various RAID levels store information in different ways. Additionally, manufacturers like Buffalo also introduce some modifications to this process, and that is why data can be written to hard disk in a wide variety of ways.
How can a NAS Buffalo TeraStation TS-8VHL/E device's caching policy impact data loss risks?
The caching policy of a NAS Buffalo TeraStation TS-8VHL/E device can impact data loss risks in several ways:
- Write caching: The device may use write caching to improve performance by temporarily storing write operations in cache before writing them to the actual storage drives. However, if there is a power failure or system crash before the data is written to the drives, the cached data may be lost, leading to potential data loss.
- Read caching: Read caching is used to improve read performance by storing frequently accessed data in cache. While read caching does not directly impact data loss risks, it can lead to data inconsistency if the cached data is outdated or corrupted. This can occur if the original data is modified or deleted after being cached but before being written back to the storage.
- RAID caching: The TeraStation TS-8VHL/E supports various RAID levels for data redundancy and protection. Some RAID configurations, such as RAID 0 or RAID 5, may use caching to improve performance. However, if a drive fails or data corruption occurs during a write operation while caching is enabled, there is a risk of data loss or data corruption as the cached data may not be properly written to the drives.
- Cache management: The caching policy and cache management settings of the device can also impact data loss risks. For example, if the cache is not properly managed or if the cache size is insufficient, it may lead to cache overflow or cache thrashing, which can result in data loss or performance degradation.
To mitigate data loss risks, it is important to consider the following:
- Ensure that the device is equipped with a reliable power supply and backup solutions, such as uninterruptible power supply (UPS), to prevent data loss due to power failures.
- Regularly backup critical data to an external storage or cloud-based backup solution to protect against data loss in case of device failure or other unforeseen events.
- Monitor the device's caching performance and ensure that the cache management settings are optimized for data integrity and performance.
- Implement appropriate RAID configurations based on your data protection and performance requirements, considering the trade-offs between performance and data redundancy.
How to take hard disks out of the NAS and connect them to a PC?
Although NAS TeraStation TS-8VHL/E can be accessed over the network, you still need to take the hard disks out of the storage device and connect them to a Windows computer. Only in this case will the software be able to scan them properly. Here is what you should do:
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Turn off the storage and disconnect it from the power supply.
WARNING! Before you start taking hard disks out of your NAS device, read the manual carefully. Incorrect actions may damage your network-attached storage and/or the hard disks within the RAID system.
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Take the hard disks out of the NAS one by one, carefully removing them from their slots. Remember that the disks are extremely vulnerable: hitting or dropping them may result in serious physical damage.
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Make sure to mark each hard disk in accordance with how they were installed inside the NAS.
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Remove the hard disks and connect them to the computer. In this video, we have explored what ports are used to connect hard disks, and what to do if there are not enough ports or connectors.
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Restoring data with Hetman RAID Recovery
This program recovers data from damaged RAID arrays and is fully compatible with Buffalo TeraStation TS-8VHL/E. The hard disks that make up the RAID contain technical information about the algorithm used to save files. When launched, Hetman RAID Recovery reads this information and puts the damaged array together. Then you can open the disk and save your files. Also, you can recover the files accidentally deleted from the network drive.
TeraStation TS-8VHL/E has 1 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;
Safe recovery from disk images
This utility lets you save an entire copy of the disk to file and then work with this image instead of the actual disk. Such feature helps to protect data on the disk from:
- Overwriting during the recovery process;
- Loss resulting from bad sectors;
- User mistakes.
To create an image, do the following:
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Make sure that you have enough free space to save the image. The image file size usually equals the disk size.
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Select the disk in the main window, and choose from the menu Tools – Save Disk. You can select multiple disks to be saved.
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When the image creation wizard starts, you can choose to save the entire disk or select only a part of it. Specify the parameters and click Next.
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At this stage, you need to choose a directory where to save the image. Choose any disk connected to this PC, or save the image by FTP.
Where are user’s files stored?
The Buffalo TeraStation TS-8VHL/E 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.
Comparison of software for RAID recovery
Product | Operating system | License type | RAID controller support | Supported file systems | Virtual RAID controller support | Data recovery from damaged RAID | File preview |
---|---|---|---|---|---|---|---|
Hetman RAID Recovery | Windows | Paid | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
DiskInternals RAID Recovery | Windows | Paid | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | No | Yes | Yes |
R-Studio | Windows, Mac, Linux | Paid | Yes, over 200 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
UFS Explorer RAID Recovery | Windows, Mac, Linux | Paid | Yes, over 1,000 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
EaseUS Data Recovery | Windows | Paid | Yes, over 20 controllers | FAT, NTFS, Ext2/3/4, HFS+ | No | Yes | Yes |
ReclaiMe Free RAID Recovery | Windows | Free | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
It is possible to recover deleted files from a NAS Buffalo TeraStation TS-8VHL/E device, but it depends on various factors such as the file system used, the type of deletion, and whether the space previously occupied by the deleted files has been overwritten.
If the files were deleted using a simple deletion method (e.g., moving to the trash or using the NAS's web interface to delete), they may still be recoverable. In such cases, you can try using data recovery software specifically designed for NAS devices to scan and recover the deleted files.
However, if the files were securely deleted or the NAS device has a feature that overwrites the deleted files immediately, the chances of recovery become significantly lower.
It is important to note that attempting data recovery on a NAS device should be done with caution to avoid further data loss. It is recommended to consult with a professional data recovery service or consult the Buffalo support team for guidance on the specific device model.