There are 10 standard RAID levels, 0 through 9. RAID levels describe the configuration of a RAID array, and relate to the patterns in which data is written to the RAID drive, the fault tolerance of the RAID array, and the space efficiency. To some degree, the RAID level can affect the number of drives in the array, but that doesn’t mean that, for instance, RAID 9 uses nine hard drives. You can run any RAID level up to 9 with just two drives.

Hybrid RAID Levels

Beyond the standard RAID levels are Hybrid RAID levels, which means two different RAID levels are “nested” within one controller. (Rarely are more than two RAID levels nested.) Hybrid RAID array configurations include designations such as RAID 0+1, RAID 1+0, or RAID 5+0. Some people may eliminate the plus sign, resulting in RAID 10 or RAID 50, but that doesn’t mean RAID “ten” or RAID “fifty.”

The number of the top array comes second in the listing, so RAID 10 means drives are combined into multiple level 1 RAID arrays, which are then treated as single drives combined into a RAID 0 configuration.

Let’s explore the very common hybrid RAID arrays of RAID 0+1 and RAID 1+0  or RAID 10.

RAID 0+1: Configured with a minimum of four hard drives, always in pairs, this highly complex hybrid RAID configuration has high fault tolerance and good performance. The array can continue operating if more than one drive fails in the same mirrored set, but not if two mirrored disks fail at the same time.

RAID 1+0: In this configuration, a RAID array will keep running as long as no mirror loses all of its drives, so it can keep running as long as there is at least one hard drive still running, offering excellent fault tolerance.

Hybrid RAID Array Data Recovery

Remember, when one hard drive in a RAID array fails, it puts added stress on the other drives in the array. Additionally, since most RAID drives are purchased and installed at the same time, they tend to last the same amount of time before nearing the end of their life span. 

If you suffer RAID failure due to the loss of one or more hard drives, cascading failure may be imminent. Make sure your mission critical data is backed up, and replace the hard drives in the array.

If it’s too late, remember that 24 Hour Data has data recovery specialists with expertise in all RAID data recovery, including hybrid RAID data recovery, standing by to help.