Today I am going to show you a new algorithm we just implemented to detect the parity location on each member drive of a RAID5.
It doesn't reply on the file system of the RAID5. It can be used for Windows RAIDs, Linux RAIDs, MAC RAIDs and UNIX RAIDs. Even though the algorithm is not giving you a complete RAID configuration, the result generated by the application will indicate the strip size and the drives' sequence. The drives' sequence is different to drives' order. For example, a RAID5 has a drives' sequence of 3-2-0-1, the drives' order can be 2-0-1-3, 0-1-3-2, 1-0-2-3, etc. It depends on which drive is the first drive and the rotation direction of the RAID5.
The example given in the video is a 4-disks Windows RAID5. According to the result, we worked out the strip size is 256 sectors and the drives' sequence is 4-3-2-1.
This algorithm becomes extremely useful to work out the RAID configuration (strip size, drives' order, header size and rotation direction)when dealing with a RAID5 created by an unknown or a strange file system. We will discuss this further on our blog in the near future.
(Designed by Zijian Xie, R&D Manager, MSc, BEng)