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System Architecture
1
I/O Configurations
The CPX8216 contains two independent 8-slot CompactPCI buses. One
slot in each bus is dedicated to a system processor, and another is needed
for the HSC. This leaves six slots on each bus to support I/O devices or
nonsystem processors.
One possible configuration is to use the CPX8216 as a high I/O
CompactPCI system with redundant CPUs. With this configuration, it is
possible to run twelve independent I/O modules within a CPX8216
system. Applications requiring dense processing power could use all
twelve I/O slots to support nonsystem processors.
Such a system would be protected against a CPU or HSC fault, but it would
be vulnerable to data losses if any of the I/O modules or nonsystem
processor modules were to fail. In systems handling critical data, it is
possible to implement a 2N or an N+1 I/O redundancy strategy that allows
the level of service to be continued in the event that a module fails.
In the case of a 2N-redundant system, each I/O module or nonsystem
processor module is matched with an identical module on the other bus.
The paired modules can be configured in an active/passive arrangement or
a load-sharing arrangement in which each carries half of the load of a
single module. In an N+1 arrangement, multiple modules are backed up by
a single spare. For example, a single passive nonsystem processor module
can be used to back up five others.
Peripherals
Power/Fan Modules
The CPX8216 system requires a minimum of two power/fan sled modules
and a fan-only sled module to provide adequate power and cooling for a
fully loaded, nonredundant system. The system can contain a third power
supply/fan sled as part of an N+1 strategy, meaning that the system can
continue providing service if one of the modules fails. These modules are
hot swappable and available for DC and AC environments.