NAS Synology RackStation RS2421RP+ / RS2421+ RAID Controller Failure: Causes, Recovery Steps, and Data Recovery Techniques

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

Can the use of specific data synchronization or replication mechanisms mitigate data loss risks for NAS Synology RackStation RS2421RP+ / RS2421+ devices?

Yes, the use of specific data synchronization or replication mechanisms can help mitigate data loss risks for NAS Synology RackStation RS2421RP+ / RS2421+ devices. Synology offers several built-in features and applications that can be utilized for data protection and redundancy.

1. Snapshot Replication: This feature allows you to take point-in-time snapshots of your data and replicate them to another Synology NAS or off-site server. Snapshots provide a quick and efficient way to restore data in case of accidental deletion, corruption, or ransomware attacks.
2. Hyper Backup: It enables you to back up data to various destinations, including local shared folders, external drives, remote Synology NAS, or cloud services like Amazon S3, Microsoft Azure, etc. Hyper Backup provides versioning and deduplication, ensuring efficient storage utilization and easy recovery of specific file versions.
3. RAID Configuration: The RS2421RP+ / RS2421+ supports various RAID configurations, such as RAID 1, RAID 5, RAID 6, and RAID 10. By configuring your NAS with RAID, you can achieve data redundancy and protection against drive failures. If a drive fails, the data can be rebuilt from the redundant information stored on other drives.
4. High Availability (HA): HA allows you to create a redundant system by pairing two RS2421RP+ / RS2421+ devices. In case of a hardware failure on one device, the other takes over seamlessly, ensuring uninterrupted access to your data.
5. Cloud Sync: This application synchronizes your NAS data with cloud storage services like Dropbox, Google Drive, or Microsoft OneDrive. By keeping a copy of your data in the cloud, you add an extra layer of protection against local data loss.

These mechanisms, when properly configured and used in combination, can significantly reduce the risk of data loss for NAS Synology RackStation RS2421RP+ / RS2421+ devices. However, it's important to regularly test and verify the backups and replication processes to ensure their effectiveness.

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

Although NAS RackStation RS2421RP+ / RS2421+ 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 Synology RackStation RS2421RP+ / RS2421+. 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 Synology

RackStation RS2421RP+ / RS2421+ 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);

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 Synology RackStation RS2421RP+ / RS2421+ 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.

Comparison of software for RAID recovery