Recovering Data After NAS Synology DiskStation DS3622xs+ RAID Controller Failure: Causes and Steps

Contents

• Why Regular Data Recovery Tools Can’t Restore Files from RAID
• Key Information About the NAS Synology DiskStation DS3622xs+
• 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 Synology 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 quality of service (QoS) settings impact data transfer reliability on NAS Synology DiskStation DS3622xs+ devices?

Quality of Service (QoS) settings can have a significant impact on data transfer reliability on NAS Synology DiskStation DS3622xs+ devices. Here are a few ways QoS settings can affect data transfer reliability:

1. Bandwidth Allocation: QoS settings allow you to prioritize and allocate bandwidth to specific applications or services. By allocating sufficient bandwidth to data transfer processes, you can ensure that they receive the necessary resources for uninterrupted and reliable transfer.
2. Traffic Prioritization: QoS settings enable you to prioritize certain types of traffic over others. For example, you can prioritize data transfer traffic over web browsing or streaming services. By giving priority to data transfer, you can minimize the chances of interruptions or delays caused by other network activities.
3. Congestion Management: QoS settings help in managing network congestion by controlling the flow of data. They can prevent network congestion from affecting data transfer reliability by prioritizing and regulating the transfer process. This ensures that data transfer processes receive adequate resources even during periods of high network traffic.
4. Packet Prioritization: QoS settings can prioritize certain types of packets within a data transfer process. By giving higher priority to critical packets, such as those carrying important file chunks or metadata, you can ensure that they are transmitted with minimal delay and higher reliability.
5. Latency Control: QoS settings can help control network latency, which is crucial for data transfer reliability. By prioritizing data transfer traffic and minimizing latency-inducing activities, such as background downloads or uploads, you can reduce the chances of packet loss and improve overall reliability.

It's important to configure QoS settings appropriately based on your network environment and requirements. By optimizing QoS settings on your NAS Synology DiskStation DS3622xs+ device, you can ensure reliable data transfer and minimize potential disruptions or performance issues.

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

Although the NAS DiskStation DS3622xs+ 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 Synology DiskStation DS3622xs+. 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 Synology

DiskStation DS3622xs+ has 12 HDD slots, and it supports the following array types:

• Synology Hybrid RAID (SHR);
• RAID 6;
• RAID 5;
• RAID 10;
• RAID 1;
• RAID 0;
• Basic;
• JBOD;

NAS supports:

• Btrfs;
• EXT4;
• EXT3 (External Disk Only);
• FAT32 (External Disk Only);
• exFAT (External Disk Only);
• NTFS (External Disk Only);
• HFS+ (External Disk Read Only);

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 Synology DiskStation DS3622xs+ network-attached storage keeps DSM (DiskStation Manager) 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