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Adapter FEX and VM Fex

I have a questions about Cisco Adapter FEX and VM Fex.
As i understand, Cisco Adapter FEX gives multiple vNIC on one mezzanine card, and each of them appears as virtual port on Fabric Interconnect.
Also, same thing for VM-FEX, each VM NIC appears as virtual port on Fabric Interconnect.

Am i right?

Thank you!

VIP Green

Adaptor FEX is I/O adaptor

Adaptor FEX is I/O adaptor virtualization, which is agnostic to the OS and therefore works in virtualized as well as non virtualized environments.


VM-FEX (also called Hypervisor Bypass) is available for different Hypervisors



    example VM-FEX for VMware ESX

    VM-FEX (previously known as VN-link) is a method to extend the network fabric completely down to the VMs. With VM-FEX, the Fabric Interconnects handle switching for the ESXi host's VMs. UCSM utilizes the vCenter dVS Application Programming Interfaces (API) to this end. Therefore, VM-FEX shows as a dVS in the ESXi host.

    There are many benefits to VM-FEX:

    • Reduced CPU overhead on the ESX host
    • Faster performance
    • VMware DirectPath I/O with vMotion support
    • Network management moved up to the FIs rather than on the ESXi host
    • Visibility into vSphere with UCSM
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