Practical RAID Array Tips for NAS Digiever DS-4236 UHD Data Restoration

Contents

• Why Regular Data Recovery Tools Can’t Restore Files from RAID
• Key Information About the NAS Digiever DS-4236 UHD
• How to Remove Hard Disks from Your NAS and Connect Them to a PC
  • Step-by-Step Data Recovery with Hetman RAID Recovery
  • How to Safely Recover Data from Disk Images
  • Where Are the User’s Files Actually Stored?
  • RAID Recovery Software: Detailed Comparison

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 RAID (Redundant Array of Independent Disks) configurations impact data loss in NAS Digiever DS-4236 UHD devices?

RAID configurations in NAS Digiever DS-4236 UHD devices can greatly impact data loss. Here are a few ways RAID can affect data loss in these devices:

1. Fault tolerance: RAID configurations provide redundancy by distributing data across multiple disks. In case of a disk failure, the data can still be accessed from the remaining disks. This fault tolerance helps minimize data loss as it allows for the reconstruction of the lost data.
2. Data protection: RAID configurations often include features like mirroring or parity, which help protect against data loss. Mirroring duplicates data across multiple disks, ensuring that even if one disk fails, the data is still available on another disk. Parity, on the other hand, calculates and stores additional information that can be used to reconstruct data in case of a disk failure.
3. Hot-swapping: Many RAID configurations support hot-swapping, which means that failed disks can be replaced without shutting down the system. This reduces the downtime and minimizes the risk of data loss during disk replacement.
4. Performance impact: Different RAID configurations have varying levels of performance impact. Some configurations, like RAID 0, offer better performance but no redundancy, which means a higher risk of data loss. On the other hand, more redundant configurations like RAID 5 or RAID 6 may have a lower performance impact but provide better data protection.

It's important to note that while RAID configurations can significantly reduce the risk of data loss, they are not foolproof. Other factors like power outages, natural disasters, or human errors can still lead to data loss. Therefore, it is recommended to have additional backup measures in place, such as regular offsite backups, to further safeguard your data.

How to Remove Hard Disks from Your NAS and Connect Them to a PC

Although the NAS DS-4236 UHD 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:

1. 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.

2. 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.

3. Label each hard disk according to its position inside the NAS. The order of the drives is crucial for correct RAID reconstruction.

4. 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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   How to Order Remote Data Recovery

Step-by-Step Data Recovery with Hetman RAID Recovery

This program restores data from damaged RAID arrays and is fully compatible with Digiever DS-4236 UHD. 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.

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How to recover data from a Digiever

DS-4236 UHD 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:

1. Ensure you have enough free space to store the image. Its size will typically match the size of the original disk.

2. In the main window, select the target disk and choose Tools - Save Disk. You can also select multiple disks if needed.

3. 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.

   

4. 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-4236 UHD 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