RAID concepts and limitations
Calculate usable capacity, know what each RAID level survives, and why RAID is never a backup.
- Level
- Intermediate
- Length
- About 40 minutes
- Contents
- 3 lessons · 1 video · final exam
- Status
- Published · updated 1 Oct 2026
Skills you'll practise
- Calculate usable capacity for RAID 0, 1, 5, 6 and 10
- State how many disk failures each level survives
- Explain rebuild risk and why RAID doesn't replace backups
- Decide safe next steps for a degraded array
Course outline
- 1.RAID levels and what they don't protectVideo · 2 min
- 2.Levels, capacity and rebuild riskLesson · 16 min
- 3.Hardware RAID, software RAID and ZFSLesson · 15 min
- 4.Living with a degraded array: rebuilds and hot sparesLesson · 15 min
- 5.RAID concepts and limitations: knowledge checkKnowledge check · 15 questions
- 6.Degraded array with a second disk warningScenario
- 7.Final exam8 questions · passing it completes the course, so people who already know the material can test out
Sources it draws on
The lessons and questions are written from these references, so learners can go back to the original.
- RAID levels 0, 1, 5, 6, 10: capacity and fault tolerance
- Rebuild risk and unrecoverable read errors on large disks
See it with your own jobs and topics
Tell us about your team and we'll walk you through setup, from choosing jobs to your first skills check.