- 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?
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.
How can quality of service (QoS) settings impact data transfer reliability on NAS Lenovo ThinkSystem SR655 Rack Server devices?
Quality of Service (QoS) settings can have a significant impact on data transfer reliability on NAS Lenovo ThinkSystem SR655 Rack Server devices. Here are a few ways QoS settings can affect data transfer reliability:
- Bandwidth Allocation: QoS settings allow you to allocate bandwidth to different applications or services. By prioritizing critical data transfers, you can ensure that they receive sufficient bandwidth, reducing the chances of congestion or data loss during high network traffic periods.
- Traffic Prioritization: QoS settings enable you to prioritize specific types of traffic, such as video streaming or VoIP, over others. By prioritizing data transfers, you can ensure that critical transfers are not affected by lower-priority traffic, improving reliability.
- Packet Prioritization: QoS settings can prioritize packets based on their importance or type. For example, you can prioritize TCP packets over UDP packets or give higher priority to control packets. This helps ensure that important data packets are delivered reliably and in a timely manner.
- Traffic Shaping: QoS settings allow you to shape the traffic flow, limiting the rate of data transfer for specific applications or services. By controlling the traffic flow, you can prevent network congestion and ensure that data transfers are reliable and consistent.
- Latency Control: QoS settings can help control latency by prioritizing latency-sensitive applications. This is particularly important for real-time applications like video conferencing or online gaming, where even small delays can significantly impact the user experience and data transfer reliability.
Overall, configuring QoS settings on NAS Lenovo ThinkSystem SR655 Rack Server devices can help optimize network resources, reduce congestion, prioritize critical data transfers, and improve overall data transfer reliability.
How to take hard disks out of the NAS and connect them to a PC?
Although NAS ThinkSystem SR655 Rack 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:
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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.
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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.
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Make sure to mark each hard disk in accordance with how they were installed inside the NAS.
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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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Restoring data with Hetman RAID Recovery
This program recovers data from damaged RAID arrays and is fully compatible with Lenovo ThinkSystem SR655 Rack 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.
How to recover data from a Lenovo
ThinkSystem SR655 Rack Server has 32 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:
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Make sure that you have enough free space to save the image. The image file size usually equals the disk size.
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Select the disk in the main window, and choose from the menu Tools – Save Disk. You can select multiple disks to be saved.
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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.
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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 SR655 Rack 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
| Product | Operating system | License type | RAID controller support | Supported file systems | Virtual RAID controller support | Data recovery from damaged RAID | File preview |
|---|---|---|---|---|---|---|---|
| Hetman RAID Recovery | Windows | Paid | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
| DiskInternals RAID Recovery | Windows | Paid | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | No | Yes | Yes |
| R-Studio | Windows, Mac, Linux | Paid | Yes, over 200 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
| UFS Explorer RAID Recovery | Windows, Mac, Linux | Paid | Yes, over 1,000 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
| EaseUS Data Recovery | Windows | Paid | Yes, over 20 controllers | FAT, NTFS, Ext2/3/4, HFS+ | No | Yes | Yes |
| ReclaiMe Free RAID Recovery | Windows | Free | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
In general, performing a system update or software upgrade on a NAS (Network Attached Storage) device should not result in data loss. However, it is always recommended to have a backup of your important data before proceeding with any updates or upgrades.
If, for some reason, you experience data loss after a system update or software upgrade, there are still potential ways to recover the data. Here are a few steps you can take:
Remember, the success of data recovery depends on various factors such as the extent of data loss, the specific NAS device, and the actions taken after the loss occurred.