RAIDi

RAIDi is a term used to describe a class of data storage architectures that extend conventional RAID by emphasizing independent disk pools, modular controllers, and dynamic reconfiguration. Unlike a single fixed RAID level, RAIDi architectures aim to combine multiple drives into scalable arrays that can be expanded, rebalanced, or migrated with minimal downtime while preserving redundancy and performance. The term is not part of any official standard and is used variably by vendors and open-source projects.

In typical RAIDi designs, a software- or firmware-based layer manages metadata about the layout across disks, while a separate I/O path handles reads and writes. Drives may include a mix of hard disk drives and solid-state drives, and the system uses parity, mirroring, or erasure-coded data to tolerate failures. Online capacity expansion, online re-striping, and automated rebuilds are common features. Some implementations separate storage into independent pools that can be accessed concurrently, potentially improving fault isolation and maintenance.

Variants and implementations of RAIDi differ in the specifics of data layout and failure tolerance. Many deploy erasure coding or distributed parity schemes, combined with dynamic reallocation of space and flexible pool boundaries. The goal is to provide scalable fault tolerance and performance while allowing modules to be upgraded or replaced without disrupting the entire array.

Reliability and performance of RAIDi depend on the chosen algorithms, drive health, and workload. Benefits often include better scalability and maintenance flexibility, whereas drawbacks can include added complexity and potential overhead. Typical use cases include large-scale data centers, enterprise storage systems, and environments requiring flexible growth with high availability.

See also: RAID, RAID levels, erasure coding, software-defined storage, distributed storage.