Each fan tray continues to operate indefinitely and provide sufficient cooling even whena single fan fails provided the room temperature is within the operating range. See“Cooling System and Airflow in a J-EX8216 Switch” on page 44.Routing Engine and Control RedundancyEach RE module contains Routing Engine circuitry, and system control and managementcircuitry. A redundant J-EX8216 switch has two RE modules. When a switch has two REmodules, one functions as the master while the other functions as a backup and is instandby mode. This provides the switch with full redundancy (1+1) for Routing Engineand system control functionality.Table 6 on page 13 lists the RE module slots in the J-EX8216 chassis and the RoutingEngine and associated system control redundancy.Table 6: Routing Engine and System Control Redundancy for J-EX8216 SwitchesRouting Engine and SystemControl RedundancySlot RE1Slot RE0Switch ConfigurationYesRE moduleRE moduleRedundant configurationSwitch Fabric RedundancyThe switch fabric circuitry in a J-EX8216 switch is distributed across eight Switch Fabric(SF) modules. We recommend that you install all eight SF modules in a J-EX8216 switchto support maximum midplane performance for the installed line cards.All SF modules are fully connected to all installed line cards. When the switch isoperational, all eight SF modules are simultaneously active. If a single SF module fails,the input/output traffic for that module is load-balanced among the remaining SFmodules, providing graceful degradation in midplane performance. The impact of an SFmodule failure on the performance of a J-EX8216 switch varies based on the type of linecards installed in the switch and the traffic mix flowing through them. In a J-EX8216switch configuration that is fully loaded with 8-port 10-Gigabit Ethernet SFP+ line cards,if one SF module fails, the remaining seven SF modules still have sufficient switchingcapacity to maintain continuous switch operation at full wire-rate performance.Table 7 on page 13 lists the SF module slots in a J-EX8216 chassis and shows that switchfabric redundancy is associated with the redundant switch configuration.Table 7: Switch Fabric Redundancy for J-EX8216 SwitchesSwitch Fabric RedundancySlots SF7 Through SF0Switch ConfigurationYesSF modules installed in all slotsRedundant configurationRelatedDocumentationRouting Engine (RE) Module in a J-EX8216 Switch on page 26•• Switch Fabric (SF) Modules in a J-EX8216 Switch on page 2913Chapter 1: Dell PowerConnect J-Series J-EX8216 Switch Overview
