Ultimate Guide to RAID Array Recovery for NAS Buffalo TeraStation TS3420DN1604

Contents

• Why Regular Data Recovery Tools Can’t Restore Files from RAID
• Key Information About the NAS Buffalo TeraStation TS3420DN1604
• 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 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.

Are there any precautions to take while replacing or upgrading hard drives in NAS Buffalo TeraStation TS3420DN1604 devices?

Yes, there are several precautions to take while replacing or upgrading hard drives in NAS Buffalo TeraStation TS3420DN1604 devices. Here are some important steps to follow:

1. Backup your data: Before replacing or upgrading any hard drives, it is crucial to back up all your important data. This will ensure that you don't lose any data during the process.
2. Power off the device: Make sure to power off the TeraStation and disconnect it from the power source before attempting to replace or upgrade the hard drives. This will prevent any electrical accidents or damage to the device.
3. Ground yourself: To prevent static electricity from damaging the hard drives or other components, it is important to ground yourself before handling the drives. You can do this by wearing an anti-static wrist strap or by touching a grounded metal object.
4. Follow the manufacturer's instructions: Refer to the user manual or documentation provided by Buffalo for specific instructions on how to replace or upgrade hard drives in the TeraStation. Each device might have slightly different procedures, so it's important to follow the manufacturer's guidelines.
5. Use compatible drives: Ensure that the replacement or upgraded hard drives are compatible with the TeraStation TS3420DN1604. Check the device's specifications or consult with Buffalo's support to determine the compatible drive models and capacities.
6. RAID configuration: If your TeraStation is configured in a RAID array, it is important to understand the RAID configuration and how it will be affected by the hard drive replacement or upgrade. Make sure to follow the appropriate steps to maintain the RAID integrity and data redundancy.
7. Handle drives with care: When removing or inserting hard drives, handle them carefully and avoid touching the connectors or circuit boards. Hold the drives by their edges to prevent any damage from static electricity or physical mishandling.
8. Secure connections: Ensure that all connections, including power and data cables, are securely attached to the new hard drives. Loose connections can cause data loss or drive failures.
9. Test and verify: After replacing or upgrading the hard drives, power on the TeraStation and perform a thorough test to ensure that the new drives are functioning properly. Check the device's interface or management software to verify the drive status and data integrity.

If you are uncertain about any step or lack technical expertise, it is recommended to seek professional assistance or consult Buffalo's support for guidance.

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

Although the NAS TeraStation TS3420DN1604 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 Buffalo TeraStation TS3420DN1604. 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 Buffalo

TeraStation TS3420DN1604 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 Buffalo TeraStation TS3420DN1604 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