NAS QNAP HS-453DX RAID Arrays: Mechanical and Logical Failures Explained

Contents

• Why can’t ordinary software tools restore files from RAID?
• How to take hard disks out of the NAS and connect them to a PC?
  • Restoring data with Hetman RAID Recovery
  • Safe recovery from disk images
  • Where are user’s files stored?
  • Comparison of software for RAID recovery

Why can’t ordinary software tools restore files from RAID?

Conventional hard disks keep user’s data by writing it to their surface in a consecutive way, and this is how an entire file is stored on a single hard disk. However, when data is written to a RAID system, a file is divided into several parts. Then these parts are written consecutively to all hard disks within such array. The size of such parts may range from 2 KB to 2 MB, so each file is stored on several hard disks at the same time.

Such approach helps to speed up read and write operations, and it is evident that saving two parts of a file having the size of 1 GB to two hard disks simultaneously is much faster than saving the same 1 GB of data to one hard disk. However, this peculiarity makes file recovery more complicated.

Various RAID levels store information in different ways. Additionally, manufacturers like QNAP also introduce some modifications to this process, and that is why data can be written to hard disk in a wide variety of ways.

Are there any precautions to take while replacing or upgrading hard drives in NAS QNAP HS-453DX devices?

Yes, there are several precautions to consider while replacing or upgrading hard drives in NAS QNAP HS-453DX devices:

1. Backup your data: Before replacing or upgrading hard drives, it is essential to back up all your data to an external storage device or another NAS. This ensures that you don't lose any important files during the process.
2. Power off the NAS: Make sure to power off the NAS and disconnect it from the power source before replacing or upgrading the hard drives. This prevents any electrical damage or data corruption.
3. Use compatible hard drives: Check the compatibility list provided by QNAP to ensure that the new hard drives you are installing are supported by your NAS model. Using incompatible drives may cause compatibility issues or performance problems.
4. Handle drives with care: When handling the hard drives, avoid dropping them or subjecting them to excessive force. Hard drives are sensitive to physical shock, and mishandling can lead to data loss or drive failure.
5. Follow the manufacturer's instructions: Read the user manual or any documentation provided by QNAP for specific instructions on how to replace or upgrade hard drives in your particular NAS model. Following the manufacturer's guidelines ensures a smooth and safe process.
6. Label and record drive information: Before removing any hard drives, label them with their respective slot numbers and record their serial numbers. This helps in identifying and organizing the drives correctly during the replacement or upgrade process.
7. Take antistatic precautions: To prevent electrostatic discharge (ESD) from damaging the hard drives, use an antistatic wrist strap or mat while handling them. ESD can cause severe damage to the sensitive electronic components of the drives.
8. Replace drives one at a time: If you are upgrading multiple hard drives, it is recommended to replace them one at a time. This allows the NAS to rebuild the RAID array or synchronize the data between the old and new drives more efficiently.
9. Verify the RAID configuration: After replacing or upgrading the hard drives, check the RAID configuration in the NAS settings to ensure that it recognizes the new drives correctly. If necessary, reconfigure the RAID array according to your requirements.
10. Monitor the NAS after the upgrade: Once the hard drives have been replaced or upgraded, monitor the NAS for any errors or issues. Check the system logs and perform regular data integrity checks to ensure everything is functioning properly.

It is always advisable to consult the official documentation or reach out to QNAP support for any specific guidelines or recommendations related to your NAS model.

How to take hard disks out of the NAS and connect them to a PC?

Although NAS HS-453DX can be accessed over the network, you still need to take the hard disks out of the storage device and connect them to a Windows computer. Only in this case will the software be able to scan them properly. Here is what you should do:

1. Turn off the storage and disconnect it from the power supply.

   WARNING! Before you start taking hard disks out of your NAS device, read the manual carefully. Incorrect actions may damage your network-attached storage and/or the hard disks within the RAID system.

2. Take the hard disks out of the NAS one by one, carefully removing them from their slots. Remember that the disks are extremely vulnerable: hitting or dropping them may result in serious physical damage.

3. Make sure to mark each hard disk in accordance with how they were installed inside the NAS.

4. Remove the hard disks and connect them to the computer. In this video, we have explored what ports are used to connect hard disks, and what to do if there are not enough ports or connectors.

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   How to Order Remote Data Recovery

Restoring data with Hetman RAID Recovery

This program recovers data from damaged RAID arrays and is fully compatible with QNAP HS-453DX. The hard disks that make up the RAID contain technical information about the algorithm used to save files. When launched, Hetman RAID Recovery reads this information and puts the damaged array together. Then you can open the disk and save your files. Also, you can recover the files accidentally deleted from the network drive.

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How to recover data from a QNAP

HS-453DX has 4 HDD slots, and it supports the following array types:

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

NAS supports:

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

Safe recovery from disk images

This utility lets you save an entire copy of the disk to file and then work with this image instead of the actual disk. Such feature helps to protect data on the disk from:

• Overwriting during the recovery process;
• Loss resulting from bad sectors;
• User mistakes.

To create an image, do the following:

1. Make sure that you have enough free space to save the image. The image file size usually equals the disk size.

2. Select the disk in the main window, and choose from the menu Tools – Save Disk. You can select multiple disks to be saved.

3. When the image creation wizard starts, you can choose to save the entire disk or select only a part of it. Specify the parameters and click Next.

   

4. At this stage, you need to choose a directory where to save the image. Choose any disk connected to this PC, or save the image by FTP.

   

Where are user’s files stored?

The QNAP HS-453DX network-attached storage keeps QTS (QuTS hero) 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.

Comparison of software for RAID recovery