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

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

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

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 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.

Comparison of software for RAID recovery