Effective RAID Array Tips for NAS Digiever DS-4120-RM Data Recovery

Contents

• Why Regular Data Recovery Tools Can’t Restore Files from RAID
• Key Information About the NAS Digiever DS-4120-RM
• 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-4120-RM devices?

RAID configurations can have a significant impact on data loss in NAS Digiever DS-4120-RM devices. Here are a few ways RAID can affect data loss:

1. Data Redundancy: RAID configurations, such as RAID 1 or RAID 5, provide data redundancy by storing multiple copies of data across multiple disks. In case of a disk failure, the redundant copies can be used to rebuild the data and prevent data loss.
2. Fault Tolerance: RAID configurations with parity, such as RAID 5 or RAID 6, can tolerate the failure of one or more disks without losing data. The parity information stored across the disks allows for data reconstruction in case of disk failures.
3. Hot Spare: Some RAID configurations support the use of a hot spare disk, which remains idle until a disk failure occurs. When a disk fails, the hot spare automatically replaces the failed disk, minimizing the downtime and reducing the risk of data loss.
4. Performance Impact: RAID configurations can impact data loss indirectly by affecting performance. For example, RAID 0 offers improved performance by striping data across multiple disks but does not provide any redundancy. If one disk fails in RAID 0, all data on that disk is lost.
5. Rebuild Process: When a disk fails in a RAID configuration, the system initiates a rebuild process to reconstruct the data on the failed disk. During this process, the system is vulnerable to additional disk failures, which can lead to data loss if there is no redundancy or backup.

It's important to note that while RAID configurations can provide some level of protection against data loss, they are not foolproof. Other factors such as human error, software issues, or natural disasters can still result in data loss. Therefore, it is recommended to have additional backup measures in place, such as regular off-site backups, to further mitigate the risk of data loss.

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

Although the NAS DS-4120-RM 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-4120-RM. 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-4120-RM 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-4120-RM 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