Steps to Recover Your NAS Thecus 1U4200XXX RAID Array When It Breaks

Contents

• Why Regular Data Recovery Tools Can’t Restore Files from RAID
• Key Information About the NAS Thecus 1U4200XXX
• 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 Thecus 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 conducting regular backups on external storage devices mitigate data loss risks for NAS Thecus 1U4200XXX devices?

Conducting regular backups on external storage devices can mitigate data loss risks for NAS Thecus 1U4200XXX devices in the following ways:

1. Redundancy: By regularly backing up data to external storage devices, you create redundant copies of your important files. In case of any data loss event on the NAS device, you can restore the lost data from the backups.
2. Protection against hardware failure: NAS devices like Thecus 1U4200XXX can experience hardware failures such as hard drive crashes or controller malfunctions. Regularly backing up data to external storage devices ensures that even if the NAS device fails, your data remains safe and accessible.
3. Protection against data corruption: Data corruption can occur due to various reasons like software bugs, power surges, or malware attacks. By regularly backing up your data to external storage devices, you can minimize the risk of data corruption. If the data on the NAS device gets corrupted, you can restore the clean backup copies.
4. Disaster recovery: In the event of a natural disaster like fire, flood, or theft, the NAS device and the data stored on it may be damaged or lost. Conducting regular backups to external storage devices allows you to have an off-site copy of your data, ensuring that you can recover your files even if the NAS device is destroyed or stolen.
5. Easy data migration: If you need to upgrade or replace your Thecus 1U4200XXX device, having regular backups on external storage devices simplifies the data migration process. You can easily transfer the backed-up data to the new device, minimizing the risk of data loss during the transition.

To ensure effective mitigation of data loss risks, it is essential to follow best practices for backups, such as performing regular backups at scheduled intervals, verifying the integrity of backups, and storing the external storage devices in a secure location.

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

Although the NAS 1U4200XXX 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 Thecus 1U4200XXX. 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 Thecus

1U4200XXX has 4 HDD slots, and it supports the following array types:

• RAID 0;
• RAID 1;
• RAID 5;
• RAID 6;
• RAID 10;
• JBOD;

NAS supports:

• EXT3;
• EXT4;
• XFS;

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 Thecus 1U4200XXX 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