 Hello everybody! Watch this video to find out how to recover data from a software BTRFS RAID based on Linux, how to create a BTRFS RAID 5, how to replace a fold-in disk, and how to recover lost data from a damaged disk RAID. Hello friends! If you need to recover deleted data, view or restore removed browser history. Hetman Software Products will help you. Follow the link in the description, download the necessary program for free, install it and analyze the disk. The utility will show you the data you can recover, so you will be able to view it or get it back. In our channel and blog you will find solutions to any problem, from installing an operating system or configuring it to fixing possible bugs and errors or optimizing mobile gadgets. Our specialists will answer any questions you ask in your comments under the videos or articles. Usually, MDADM and LVM are used to create a RAID system in Linux, and you can learn more about it in other videos on our channel. In addition to these tools, you can also find integrated RAID support in BTRFS file system. This system uses its own features to create and manage disk arrays, and we are going to study them in detail. BTRFS is a modern file system with an integrated copy and write feature and RAID support. The essence of copy and write is that when you copy existing files, they don't overwrite old data, which makes it much easier to recover after crashes or failures. As interruptions in the write operations don't affect the previous state of data. BTRFS stores metadata separately from the file system data, and its main advantage is that you can use various RAID levels for data and metadata. Another purpose of this journal file system is to provide a more effective way to manage the storage system and improve data integrity features in Linux. Before you can start using BTRFS, you need to install special tools to manage this file system. Do it with a following command. You have to create a mall on point directory for BTRFS file system before you can build a RAID array. Use this command to create the directory, where data is the directory name. Now you can start building the array. This file system doesn't require a hard disk to be divided into partitions if you want to build a RAID. But there is more. When building a disk array, you can use physical hard disks, their partitions, and even combine disks and partitions into a single array. For illustration, I'll show you how to use five hard disks to create a RAID 5 system. To save the trouble of having to enter the root password every time, run the sudo i command and type the password, and now you can run all commands as administrator. To build the RAID system, type this command in the terminal. Here L is the mark or name of the file system, and the parameters that can be used are D to set RAID 5 for file system data and M to set RAID 5 for file system metadata, and F to force BTRFS file system even if one of the drives has a different file system. After that, you can mount BTRFS RAID using any of the drives included into your array. In my case, I used five drives to create a disk array – SDB, SDC, SDD, SDE, and SDF. That is why I can mount file system data with the help of drive SDB in the directory with the name data. Open the disk management tool and mount the drive, and then it becomes available. Otherwise, you can use the form and command to mount the drive. To check if everything is okay, run the command sudo dfh. Now you can see the BTRFS RAID system mounted in the directory with the name data. To view information on how the operating system uses this array, that is, how much space is free and occupied, type this command. To unmount the array, you only need to use a single command. To replace the drive, there is a BTRFS replace command. It is run asynchronously, and that is why the first parameter gives the command start to launch the process, cancel to stop it, and status to see its progress and condition. First of all, you need to identify the number of the damaged drive with the help of this command. Then replace it with the new one using this command, where 3 is the number of the missing drive. SDG is the code for a new drive. To recover a damaged BTRFS system, use the mount option Recovery by entering the following command. Start the recovery process. Even the most reliable and full-tolerant system may fail some day. As system error, drive failure, hardware issues, damaged metadata, accidental removal or wrong settings, any of these may result in knocking the RAID down and making it lose important information. If you face anything from that list, just use Hetman RAID Recovery. It can restore data from non-operational RAID systems or from drives that used to be part of such systems. For utility, we'll read all available information about the RAID and then rebuild the damaged RAID so that you can copy all the discovered data from there. Connect the drives to a Windows computer, use a virtual machine, or install Windows alongside your main Linux operating system. The utility will scan the drives automatically and display all the information about your RAID. As you can see, in case with BTRFS RAID, the program doesn't collect the drives into a single RAID. This can be explained by peculiarities of building this RAID type, but all the information is stored according to the RAID type which is used. To start the recovery process, open the Drive Manager, right-click on any drive that used to make up this RAID and run the file scan. When scanning any drive, the results should be the same as all of them are elements of the same disk RAID. When the scan is over, the program will display the file it has found. The preview feature will help you find the required images or videos more easily. Select the files you want to recover, click Recovery, select what you want to save them, and click Recovery again. In the end, you will find the recovered files in the folder you have chosen. If the fast scan can't find the required files, then go for full analysis. This scan type takes much longer, but it's sure to find all the information still existing on the drive, even if it was removed a long time ago. As this is a RAID 5 system, all the information remains intact in spite of one drive missing. But if two drives go south, a part of the data is bound to be damaged. BTRFS supports data compression at the file system level. It means that the information available on the disk will be compressed automatically as more new data is written. When accessing files stored in the file system, the data of such files will be decompressed automatically. The file system feature helps to save disk space and your time, because you don't have to look for a third-party tool for compressing your files. BTRFS supports three main file compression methods, ZLIB, LZO, and ZSTD. They differ by the degree and speed of compression. Over-utility supports recovery of files compressed with any of these methods. In the Procopy interface, compressed volumes and files are shown like this, highlighted in a different color. Another serious advantage of BTRFS file system is its ability to create sub-volumes. In plain English, you can create, for example, three different disks sub-volumes on one hard disk. These sub-volumes may expand and the cost of free space is taken from another volume. When necessary, this feature lets you expand one disk at the expense of another without either compressing or transferring the actual data. These sub-volumes are then displayed like this. In the Procopy interface, you can create sub-volumes as disks inside the main drive. In the same way, folders containing snapshots are displayed. Here is the command used to create sub-volumes. To view the list of sub-volumes on this drive, run the following command. And this one to mount a sub-volume. Where SDB1 is the drive code. There are only a few data recovery tools capable of reading BTRFS rate systems. That information may be erased during the scan, so having an option to create an image of the array and then run the scan on the image instead of the actual set of disks could be a serious advantage. All in all, though, the best way to avoid losing important data is to backup your files regularly. And that is all for now. Hopefully, this video was useful. Remember to click the Like button and subscribe to our channel. Push the bell button to receive notifications and never miss new videos. Leave comments to ask questions. Thank you for watching. And good luck.