 Hello everybody! Watch this video to see how to recover data from a RAID-Z array. How to build RAID-Z and RAID-Z2 arrays using the example of a device running TrueNAS operating system. And how to get data from a damaged RAID array. Or how to recover it if such data is lost, accidentally removed, or destroyed by formatting. The FS file system offers its own version of a software-based RAID known as RAID-Z. In addition to a certain performance boost, it can also fix slightest aspects of data corruption. To monitor the situation, it detects bad blocks by using checksums and then corrects logical errors immediately. This feature helps the array to maintain integrity for all of its data. However, even the most reliable file system and equipment cannot completely guarantee your data against software and hardware failures. In this video, you'll see how to recover lost data from the ZFS file system and RAID-Z array using it. ZFS is an open-source file system which is mostly used in FreeNAS storage systems and other solutions based on FreeBSD. The data distribution mechanism in RAID-Z is similar to the conventional RAID-5, but it uses dynamic striping instead of fixed-width stripes. The information about the size of each stripe is written to metadata. Due to the dynamic nature of this file system, its data can only be recovered if the metadata is not damaged. ZFS has been developed with reliability in mind, which is achieved by using various features such as copy and write, redundant metadata, journaling, and others. Because of the complicated structure of this file system, conventional data recovery tools are useless when it comes to restoring information from RAID-Z arrays. However, Hetman RAID Recovery can analyze its metadata to identify the proper structure of RAID-Z and then rebuild the damaged RAID automatically. For status, let's explore how to create a RAID-Z array with the example of a storage device with the TrueNAS operating system. In the previous video, I have already demonstrated how to install and configure such operating system and how to create a RAID-Z. Now, let's find out how to build RAID-Z2, that is, an array of the second level. Start by accessing the TrueNAS Management menu and expanding the tab Storage, Pools. Here click the button Add and then Create Pool. Give the Pool name and select Disks. For RAID-Z2, you need at least 4 disks, and then click on this arrow below to add storage devices to the list. Choose the drives here and select the RAID level from the drop-down list. Then click Create. In the pop-up window, saying that all data will be erased, check the box here and click Create Pool. And install the process of formatting the drives and building the RAID. To create a valid simulation of a typical scenario, let's configure an FTP connection. Add data to the RAID array, then imitate a sedation involving loss or failure of the storage device so that the data inside is no longer accessible. Let's begin by adding a new dataset for FTP connection. Open the tab Storage, Pools, hit the 3 dots button, add dataset. Assign a name, don't change other settings and click Submit. Add a new user for FTP, Accounts, Users, Add. Give the name and password, uncheck the box next to New Primary Group, and choose FTP from the list. Then select the directory we have created before, set the required permissions and save the settings by clicking Submit. Let's go back to the dataset we have created and modify the permissions. Click on the 3 dots button, add it permission. Choose the user, FTP and Group, FTP, check the box here, confirm it. Then check the boxes for Apply User and Applying Group, then save the settings. Now the last step is to enable the FTP server. Open Services, drag the slider to the Enabled position and check the box for automatic startup. The FTP connection is configured, so let's check access in the Explorer. In the address bar, type the IP address of the server and then the user's login and password. Now you can create a folder here and write some data there. Now let's explore how to recover some information that was removed accidentally from a RAID Z array. RAID Z1 makes sure that every unique block of data is written so that recovery is possible if any of the drives suffers a failure or breakdown. In this case, data is distributed across the array in the most optimal way. RAID Z1 is very similar to RAID 5 as it uses single parity data storage pattern and it is designed to survive losing one of the disks in its array. But as I said before, only a few data recovery tools can handle this specific RAID type. Hetman RAID Recovery supports the ZFS file system and RAID Z arrays of all levels. This program can automatically rebuild a RAID system created with the help of that file system. This is a comprehensive solution for NAS-Data Recovery to help you restore your files in a number of different scenarios. It supports most popular file systems including those used in RAID devices. For recovery, take the disks out of the server and connect them to a Windows computer. If your motherboard doesn't have enough ports to connect all the drives, there are all kinds of various adapters and expansion cords to fix this problem. The program will scan the disks for service information automatically and then it will rebuild the RAID system on the fly. As you can see, my RAID Z array is displayed in the Drive Manager. To start the recovery process, analyze the drive. Right-click on the array, open, Fast scan. As we can see, with Fast scan, the program didn't manage to find the deleted files, and the files which are still on the disks are all available for recovery. The bottom line is that Fast scan will help you to get your data back in case of a hardware error or when your storage system breaks down. The metadata structure in the ZFS file system and RAID Z is designed in such a way that the Fast scan algorithm cannot find the deleted data because all information about it is erased from the journal. That is why you need to run full analysis in order to find the deleted files. Right-click on the partition, select Analyze again, and go for Full Analysis. Choose the file system, Next, and wait until the scan is over. This process can be quite long and the actual time required to complete it depends on the size of your array. When the scan is over, browse to the directory where the deleted files used to be and find the ones you need to recover. For your convenience, there is a feature to search for files by name. Also, you can check the contents of a file with the Preview option. As you can see, the program managed to find all the files that have been removed from the disk. As the final step, select the ones you need and click Recovery. Don't forget to select where exactly the file has to be saved. We don't recommend sending them to the same disk, so make sure you have another storage device to put your recovery data to. When the recovery process is over, you'll find all of the files in the folder you have chosen. In order to recover any information from RAID Z2, that is S2nd Level array, you also need to connect its disks to a Windows computer and then run Hetman RAID Recovery. RAID Z2 is more failure-resistant and it uses the two parity blocks and two data blocks for every single bunch of data. It is similar to RAID 6 and it can survive even if two disks are down. In RAID Z2, you are required to use at least four disks. So if your computer doesn't have enough ports to connect all disks, you can easily exclude two of them from the array. Alright, here is a case of a RAID array, which was damaged because of the server or controller failure. As you can see, the program was able to rebuild the RAID even though two disks are missing. Right-click on the RAID and run Fast scan. As a result, you can see the files which are still on the disk. Select the ones you need to restore and do it. If the program failed to find certain files, they may have been erased. In this case, try full analysis. This will enable the program to find the data even if it was removed. As a result of this testing, Hetman RAID Recovery was able to find 100% of data from a RAID Z array based on the ZFS file system and deploy it on a TrueNAS server. The program managed to recover files in their original form without any damage or loss of quality. Hetman RAID Recovery will help you recover lost data if files are removed accidentally from a hard disk inside a NAS system, if a hard disk is formatted, or the disk array is misconfigured. If there are any firmware issues, software errors, or another scenario is involving loss of data or loss of access to the network drive or damage to the RAID volume. And that is all for now. Hopefully, this video was useful. Remember to click the Like button and subscribe to our channel. Leave comments to ask questions. Thank you for watching. Good luck. While you are watching this video, civilians in Ukraine are dying from attacks in bombardments of the Russian Federation. Putin's insane regime has attacked a peaceful country in the very heart of Europe. Support the Ukrainian army by making a contribution to the font Come Back Alive. Use the QR code of the link below the video to transfer any amount of money that will boost Ukrainian resistance and help it counter Russia's designable invasion.