RAID Levels – Practice part

Task 1 – Determining storage capacity needed to copy the recovered data

Depending on the array type, a data recovery technician can easily estimate how much disk space is needed to copy the recovered data. For example, if a client brought a 3-disk RAID5 consisting of 1TB disks, it is immediately clear that only 2 TB of disk space is required since in a RAID5 the capacity of one member disk, 1 TB in this case, is used to store parity data rather than user data. In this task, you are offered to estimate the storage capacity needed to copy the recovered data for the following cases:

  1. A client brought four 2 TB disks from a RAID10. How much disk space you should have to copy the data off the RAID?
  2. A client brought a 5-disk RAID6, the capacity of each disk is 500 GB. How much disk space you should have to copy the data off the RAID?
  3. A client brought a RAID5 with delayed parity, consisting of three disks, 2 TB each. One of these three is mechanically damaged. How much disk space you should have to copy the data off the RAID?

Task 2 – Determining RAID type based on the Disk Management screenshot

Sometimes data recovery technicians do not pay enough attention to the capabilities of the standard Windows tools like Disk Management, Performance Monitor, Event Viewer, and so on. However, applying knowledge how one or the other RAID is organized (what is the minimum number of disks, how data is distributed over RAID member disks, and so on) and just looking at the Disk Management console, you can guess the RAID type you deal with. In this task, you are offered to guess the RAID level by looking at the Disk Management screenshot. If you do not know how to approach the problem or, vice versa, think that the array type is obvious, please go to the answers at the bottom of this page.

Keep in mind that disks on both screenshots came from one of the most commonly used RAID types – RAID0, RAID5, or RAID10.

Screenshot 1

Screenshot 2

Screenshot 3

What we did in these situations

For a reference point, see what we did and what we were able to figure out - download PDF with our notes here.