RAID and Subsystem Architectures
Assigning Hosts to Storage
The ratio of storage ports to a single host port
Higher availability in the event of failure
Fan-out ratio = 4:1
4 Storage ports to 1 Host port
In some configurations, usually for resilience and data protection, a server will
connect to the multiple storage ports via it’s own host port. Fabric designs
provide the ability to connect several storage ports to a single host port
through one or more fabric switches. Note that the fan-out ratio is merely the
ratio of storage ports to a single host port. It is a simple ratio that doesn’t take
into account throughput calculations.
The Fan-out ratio of each host port is determined by the zoning configuration
and is the ratio of the storage ports that can connect to the host port.