NEC 320Lb-R manual System Components and Module Set, CPU Modules, PCI modules, Feature Description

System Components and Module Set

The following sections describe the system components and module sets inside the server.

CPU Modules

The server has two CPU modules that provide Dual Modular Redundancy (DMR). The CPU modules are numbered 1 and 2, left to right as seen from the front of the tower system. The CPU modules are numbered 1 and 2, top to bottom as seen from the front of the rack-mount system. See Figure 1-4. Each CPU module has two status indicators that are listed along with a description of each in Table 1-3. Table 1-7 summarizes the features of a CPU module.

	Table 1-7. Features of the CPU Module
Feature	Description
Upgradable	Two processor sockets are available on the CPU board for one or two
multiple processor	processors.
slots
Upgradable	Six DIMM sockets on the CPU board. Can contain a minimum of 256 MB up
memory	to a maximum of 3 GB of Synchronous Dynamic Random-Access (SDRAM)
	two-way interleaved system memory.
SMP	Supports two-way Symmetric Multiprocessing (SMP) when two processors
	are installed.
Fans	Three integrated fans that provide cooling for the CPU module.

The system runs identical applications in both CPU modules in lockstep. Thus, if one CPU module fails, the second CPU module takes over the processing without any interruption to the current application running on the system. Note that this type of failure is transparent to the user.

In simplex mode the system is operating with only one CPU module and one PCI module. Thus, the failure of one CPU module or one PCI module causes the whole system to fail. A fault-tolerant system should not run in the simplex mode for any longer than necessary for upgrading or repair.

PCI modules

The server has two PCI modules that are CRUs, hot pluggable, and fault-tolerant. Each PCI module contains a PCI board that transfers data from PCI devices to the CPU. The PCI module is fault-tolerant such that if one stops functioning the other PCI module takes over.

The PCI modules are numbered 1 and 2, left to right as seen from the front of the tower system. The PCI modules are numbered 1 and 2, top to bottom as seen from the front of the rack-mount system. See Figure 1-4. Each PCI module includes four status indicators that are listed along with a description of each in Tables 1-1 and 1-2. Table 1-8 summarizes the features of a PCI module.

1-22 System Overview