Raid 1 recovery without data loss
RAID 1 recovery without data loss is possible if one of the drives in the array remains operational. In case of failure of one of the disks, the other continues to function and contains a complete copy of all data.
To begin the process, you will need a healthy spare hard drive of the same size or larger to replace the damaged drive. When connecting a new disk, the system controller should automatically restart the rebuilding (restoration) of the array using the available data on the working drive.
However, before performing any installation operations, you should consult a specialist or contact the support service of your server hardware/RAID controller. They can offer instructions and guidelines specific to your hardware model.
If you do not have experience working with software complexes of information storage such as mdadm (Linux), Disk Management Utility (Windows) or LVM2 - the best solution will be to order the services of a professional specialist or a company service team.