Array generally fall into one of two categories, monolithic and modular.
Integrated Array:
1. Monolithic array are sometimes called integrated arrays, enterprise arrays, or cache centric arrays.
2. Monolithic storage systems are generally aimed at the enterprise level, centralizing data in a powerful system with hundreds of drives.
Characteristics of integrated array:
- Large storage capacity.
- Large amount of cache to temporarily store I/Os before writing to disk.
- Redundant components for improved data protection and availability.
- Many built in features to make them more robust and fault tolerant
- Usually connect to mainframes or very powerful open systems hosts.
- Multiple front end ports to provide connectivity to multiple server.
- Multiple back end fibre channel or SCSI RAID controllers to manage disk processing.
- Expensive.
Modular Array:
1. Modular storage system provide storage to a smaller number of windows or UNIX servers then the larger integrated storage system.
2. Modular storage system are typically designed with two controllers, each of which container host interface, cache, RAID processors and disk drive interface.
Characteristics of Modular array:
- Small companies/department level.
- Smaller disk capacity and less global cache.
- Takes up less floor space and costs less.
- Can start with a smaller number of disks and scale as needed.
- Fewer front end ports for connection for server.
- Performance can degrade as capacity increases.
- Cannot connect to mainframe.
- Limited redundant and connectivity.
- Usually have separate controllers from the disk array