RAID combines multiple drives into one logical unit for speed, redundancy, or both.

The common levels

RAID 0 – Striping

Spreads data across drives for speed. No redundancy: if one drive fails, everything is lost. Never use for important data.

RAID 1 – Mirroring

Two drives hold identical data. Survives one drive failure. Simple and reliable, but you get only half the capacity.

RAID 5 – Striping with parity

Needs at least three drives and survives one failure. Good capacity efficiency, but slower writes and risky with very large drives due to long rebuild times.

RAID 6 – Double parity

Needs at least four drives and survives two failures. Safer than RAID 5 for large arrays, with some write performance cost.

RAID 10 – Mirrored stripes

Needs at least four drives. Combines speed and redundancy, and is often the best choice for databases and virtualization. Costs 50% of raw capacity.

Quick guide

Use	Common choice
Small server, OS drives	RAID 1
File server, moderate capacity	RAID 6
Databases, virtual machines	RAID 10
Temporary scratch data	RAID 0

Critical reminders

– RAID is not a backup. It doesn’t protect against deletion, corruption, ransomware, or fire.

– Replace failed drives immediately and use hot spares if possible.

– Monitor array health and alerts.

– Use matching enterprise-grade drives where possible.

DBR Soft configures resilient storage and backup solutions tailored to your risks. Contact us for more information.