Grouping drives for speed or resilience, by mirroring (level 1) or parity (level 5), say. Software-defined versions come from Storage Spaces, and Storage Spaces Direct expects pass-through controllers.
Also called redundant array of independent disks.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains RAID in context, with comparison tables and the common traps.
Terms in this definition
- Mirroring
A way of keeping a copy of an outside database, for example Azure SQL Database, Cosmos DB or Snowflake, continuously up to date in OneLake as Delta tables inside a mirrored database. You query it in T-SQL via its SQL analytics endpoint, and the replication compute costs nothing.
- General-purpose v1
The older storage account kind (
Storage), which lacks access tiers, Archive and premium file shares and retires on 13 October 2026. Converting to ZRS requires first upgrading to GPv2, a one-way change. - Storage Spaces Direct
Combines the internal drives of between two and 16 servers in a cluster into highly available, software-defined storage. It is part of Windows Server Datacenter.
Related terms
- HBA
Host bus adapter: connects a server to storage. For Storage Spaces it must pass disks straight through, so a RAID controller is no good.
- JBOD
Just a bunch of disks: an enclosure that exposes each disk on its own without RAID, the kind standalone Storage Spaces uses.
- vSAN storage policy
Storage policy with rules specific to vSAN, for example stripe count, space reservation, RAID level and FTT, determining where vSAN puts a VM's objects and how it protects them.