N+1
Redundancy ensures maximum uptime and continuous
availability.
Symmetra® achieves N+1 redundancy through a new power
sharing technology. Power sharing means that all of the modules in a
Power Array™ run in parallel and share the load evenly. N+1
redundancy means running one extra module than necessary to support
your full load. In this way, all of the modules support one
another.
For example, if your computer load is 15kVA, you achieve N+1 with
five Power Modules. If a module fails or is removed, the other
modules instantaneously begin supporting the full load. It does not
matter which module fails because all of the modules are always
running and supporting your load.
N+1 redundancy is used today in disk arrays, in processor power
supplies, and in processors themselves. But, until now, N+1
redundancy has never been offered for server level power protection.
As use of critical applications and databases increase, the
Symmetra® Power Array™ brings glass house reliability to
the mid-sized power protection range. | 
