Ever wonder if all the sectors of a volume are actually readable? Ever wonder if each disk in a mirror or RAID volume contains exactly the correct information? SoftRAID has the ability to validate volumes. This function uses the RAID engine. It reads every sector of a volume at the device level, bypassing the file system cache. This allows us to ensure that all the sectors on your volume can be read. Since the RAID engine is part of the SoftRAID driver, you can keep validating a volume even if the SoftRAID application is not running.
On mirror and RAID 1+0 volumes, the RAID engine goes one step further. After reading the sectors from each disk for the mirror volume (or mirror pair for RAID 1+0), the RAID engine compares the data from each disk to ensure that they are identical. If the RAID engine finds that a disk does not match the other mirror disks (or other disk in its mirror pair for RAID 1+0), it will write the correct information out to that disk.
On RAID 4 and RAID 5 volumes, the RAID engine computes the parity information for each block of the volume. It then compares the newly computed parity information with the parity information which is stored on the volume’s disks. If the parity information stored on the disks is incorrect, the RAID engine will write the correct parity information for that block out to the disks.