RAID Array Recovery on NAS Thecus N2200EVO: Steps to Take When It Breaks

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 Thecus also introduce some modifications to this process, and that is why data can be written to hard disk in a wide variety of ways.

How can quality of service (QoS) settings impact data transfer reliability on NAS Thecus N2200EVO devices?

The quality of service (QoS) settings on NAS Thecus N2200EVO devices can impact data transfer reliability in several ways:

1. Bandwidth allocation: QoS settings allow you to prioritize certain types of network traffic over others. By allocating more bandwidth to critical data transfers, such as backups or video streaming, you can ensure their reliability and reduce the chances of interruptions or packet loss.
2. Traffic shaping: QoS settings can shape network traffic by limiting the bandwidth for specific applications or devices. This can help prevent any single application or device from monopolizing the available bandwidth, ensuring a fair distribution of resources and maintaining data transfer reliability for all users.
3. Latency management: QoS settings can also help manage latency or delay in data transfers. By prioritizing time-sensitive applications or traffic, such as VoIP calls or video conferencing, you can minimize latency and ensure smooth and reliable communication.
4. Error correction and packet prioritization: QoS settings can prioritize error correction mechanisms, such as forward error correction (FEC), which can enhance data integrity during transfers. By prioritizing error correction packets, the QoS settings can help mitigate any potential data loss or corruption, improving overall reliability.
5. Network congestion management: QoS settings can help manage network congestion by prioritizing certain types of traffic during peak usage periods. By ensuring that critical data transfers receive preferential treatment, QoS settings can minimize the impact of congestion on data transfer reliability.

In summary, QoS settings on Thecus N2200EVO devices can impact data transfer reliability by allocating bandwidth, shaping traffic, managing latency, prioritizing error correction, and mitigating network congestion. These settings enable you to optimize the NAS device's performance and ensure reliable data transfers for various applications and users.

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

Although NAS N2200EVO 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.

   Go to view

   

   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 Thecus N2200EVO. 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.

Go to view

How to recover data from a Thecus

N2200EVO has 2 HDD slots, and it supports the following array types:

• RAID 0;
• RAID 1;
• JBOD;

NAS supports:

• EXT3;
• EXT4;
• XFS;

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 Thecus N2200EVO 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.

Comparison of software for RAID recovery