How to Recover Lost Data from a NAS Lenovo ThinkSystem SR850 Mission-Critical Server Device

Contents

• Why Regular Data Recovery Tools Can’t Restore Files from RAID
• Key Information About the NAS Lenovo ThinkSystem SR850 Mission-Critical Server
• 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 Lenovo 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 specific precautions to take while migrating data between NAS Lenovo ThinkSystem SR850 Mission-Critical Server devices?

Yes, there are several precautions to consider while migrating data between NAS Lenovo ThinkSystem SR850 Mission-Critical Server devices. Here are some important ones:

1. Backup Data: Before initiating any migration process, it is crucial to create a backup of all the data on the source NAS device. This ensures that in case of any unexpected issues or data loss during the migration, you can restore the data from the backup.
2. Plan the Migration: Develop a detailed migration plan that includes the steps involved, estimated downtime, and any potential risks. This will help you streamline the process and minimize any potential disruptions.
3. Validate Compatibility: Ensure that the target NAS device (Lenovo ThinkSystem SR850) is compatible with the source NAS device. Check the specifications, supported protocols, and compatibility matrix provided by Lenovo to ensure a smooth migration process.
4. Network Considerations: Assess the network infrastructure and bandwidth between the source and target NAS devices. If the data volume is substantial, consider using a dedicated network connection or increasing the bandwidth to expedite the migration process.
5. Allocate Sufficient Time: Depending on the data volume and network speed, the migration process may take a significant amount of time. Plan accordingly and allocate sufficient time for the migration to avoid rushing or interrupting the process.
6. Test the Migration: Before migrating the entire dataset, it is advisable to perform a test migration with a smaller subset of data. This allows you to identify any potential issues or conflicts that may arise during the actual migration and make necessary adjustments.
7. Monitor the Migration: During the migration process, closely monitor the progress and ensure that the data is being transferred correctly. Use monitoring tools provided by Lenovo or third-party software to track the migration status and identify any anomalies.
8. Verify Data Integrity: Once the migration is complete, verify the integrity of the migrated data on the target NAS device. Compare it with the backup or the source NAS device to ensure that all data has been successfully transferred without any corruption or loss.
9. Update DNS and Network Configuration: If the IP addresses or network configuration of the NAS devices change after migration, update the DNS records and any relevant network settings to ensure seamless access to the migrated data.
10. User Communication: Inform users about the migration process, expected downtime, and any temporary changes in accessing the data. Provide clear instructions on how to access the data on the new NAS device after migration.

By following these precautions, you can minimize the risks and ensure a successful data migration between NAS Lenovo ThinkSystem SR850 Mission-Critical Server devices.

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

Although the NAS ThinkSystem SR850 Mission-Critical Server 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 Lenovo ThinkSystem SR850 Mission-Critical Server. 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 Lenovo

ThinkSystem SR850 Mission-Critical Server has 24 HDD slots, and it supports the following array types:

• RAID 0;
• RAID 1;
• RAID 5;
• RAID 6;
• RAID 50;
• RAID 60;
• 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 Lenovo ThinkSystem SR850 Mission-Critical Server network-attached storage keeps LifeLine 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