RAID 10: How many disk drives should you use?
The minimum number of drives required for RAID 10 is four. RAID 10 should not be confused with RAID 0+1, which involves creating two RAID 0 stripe sets and then mirroring them.
The minimum number of drives required for RAID 10 is four. RAID 10 disk drives are a combination of RAID 1 and RAID 0, the step of which is to create a number of RAID 1 volumes by mirroring two drives together (RAID 1). The second step involves creating a stripe set with these mirrored pairs (RAID 0). In its original form this was called RAID 1+0, but has been abbreviated to RAID 10. If you had any less than four drives you would only be able to make a single RAID 1 mirror set.
RAID 10 should not be confused with RAID 0+1, which involves creating two RAID 0 stripe sets and then mirroring them. They have very similar characteristics and use the same number of drives, but are not the same.
Related Q&A from Steve Pinder
Adding an old hard drive to RAID sets on servers
When adding an old hard drive to RAID sets on servers, it’s important to account for factors such as the number of drive bays in the host. See how to... Continue Reading
Choosing a RAID level depends on capacity needs and data criticality
In this Ask the Expert, Steve Pinder talks about which RAID level to choose, depending on the criticality of your data or the capacity required. Continue Reading
RAID 5 explained: Sharing a 10 MB file among 5 drives
Find out how RAID 5 handles sharing data shares data in a 10 MB file among five drives, including how striping and parity data figure into the ... Continue Reading