Which two actions do you perform when connecting a FEX to a parent switch? (Choose two.)
A. Assign a chassis ID to the FEX.
B. Configure a vPC between the parent switch and the FEX.
C. Preconfigure the FEX.
D. Add the serial number of the FEX to the parent switch.
E. Associate the FEX to the connected interface.
The answer is A and E
Answer is A & E. A vPC is not required.
“The Fabric Extender may connect to the switch through a number of separate physical Ethernet interfaces or at most one EtherChannel interface.”
“By default, the switch does not allow the attached Fabric Extender to connect until it has been assigned a chassis ID and is associated with the connected interface.”
This example shows how to associate the Fabric Extender to an Ethernet interface on the switch:
switch# configure terminal
switch(config)# interface ethernet 1/40 (Specifies an Ethernet interface to configure)
switch(config-if)# switchport mode fex-fabric (Sets the interface to support an external Fabric Extender)
switch(config-if)# fex associate 100 (Associates the chassis ID to the Fabric Extender unit attached to the interface)
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus2000/sw/configuration/guide/rel_4_0_1a/NX2000CLIConfig/FEX-Config.html