-control is off, output flow-control is off Rate mode is dedicated Switchport monitor is off Last link flapped 00:03:48 [ (--output truncated-- As you might expect from looking at the physical module, only the first port in a port group can be configured in dedicated rate mode: Nexus Design Features NX-7K-1-Cozy(config-if)# int e7/1, e7/3, e7/5, e7/7 NX-7K-1-Cozy(config-if-range)# rate-mode dedicated ERROR: Config not applied on all ports. Config allowed only on the first port in each port group. On a Nexus 5548 switch, where all ports are capable of wire speed, each port is in dedicated mode and cannot be changed. Here's the output from a 5548's show int brief command, which shows each port with a (D) flag: NX-5548# sho int brie Ethernet Type Mode Status Reason Speed Interface Eth1/1 eth access down SFP validation failed 10G(D) 10 Eth1/2 eth access down SFP not inserted 10G(D) 10 Eth1/3 eth access down SFP not inserted 10G(D) 10 Eth1/4 eth access down SFP not inserted 10G(D) 10 Eth1/5 access down SFP not inserted 10G(D) 10 Eth1/6 eth access down SFP not inserted 10G(D) 10 Eth1/7 eth access down SFP not inserted 10G(D) 10 Configuring Fabric Extenders (FEXs) There are two ways to attach FEXs to upstream switches. The first method is called passthru mode, and looks like the diagram in Figure 18-14. In this topology, each FEX should be thought of as a blade in the switch to which it is connected. Virtual Chassis #1 Virtual Chassis #2 Figure 18-14. FEXs attached in passthru mode The second topology for FEX attachment is called crossover mode, and is shown in Figure 18-15. This method looks more like a traditional multiswitch network, but re- member, FEXs are not switches, they are fabric extenders. While this topology has merit in that each FEX is now connected to two upstream devices, the risks of such a design, in my opinion, outweigh this benefit. The only time I recommend crossover configuration is if the servers being connected to the FEXs will not be dual-homed. Chapter 18: Cisco Nexus Figure 18-15. FEXs attach