The Operating System Layer

This layer reveals whether the firewall is loaded with sufficient hardware resources to enable optimum performance (see Figure 1). 

Figure 1 : The tests associated with the Operating System layer of a Cisco PIX firewall

To know how to configure the CiscoCpu, CiscoFan, CiscoMemory, CiscoVoltage, CiscoTemperature, and CiscoPowerSupply tests, refer to in the Monitoring Cisco Router.