Simple definition
RAID combines several discs to continue to work after some of them fail, depending on the level chosen.
Technical definition
RAID 1 make a mirror, RAID 5 distributes parity and RAID 6 two parities. RAID 10 combines mirror and interlacing. It protects from disk failure, but not from removal, from a ransomware or a sinister.
What is it used for ?
Improve server storage availability and NAS.
Practical example
One NAS in RAID 6 can withstand simultaneous failure of two discs before losing volume.
Common issues
- RAID confused with backup
- very long reconstruction
- Discs of the same series failing together
- Undocumented controller or configuration
Related terms
NAS · Backup · Replication · Ransomware · Virtual machine
Key takeaway: This entry explains the general operation of the term. Exact settings may vary depending on software, vendors and environments.