Layer 2 Host Interfaces
The Fabric Extender provides connectivity for computer hosts and other edge devices in the network fabric.
Follow these guidelines when connecting devices to Fabric Extender host interfaces:
•
All Fabric Extender host interfaces run as spanning tree edge ports with BPDU Guard enabled and you
cannot configure them as spanning tree network ports.
•
You can connect servers that use active/standby teaming, 802.3ad port channels, or other host-based
link redundancy mechanisms to Fabric Extender host interfaces.
•
Any device that is running spanning tree connected to a Fabric Extender host interface results in that
host interface being placed in an error-disabled state when a BPDU is received.
•
You can connect only virtual switches that leverages a link redundancy mechanism not dependent on
spanning tree such as Cisco FlexLink or vPC (with the BPDU Filter enabled) to a Fabric Extender host
interface. Because spanning tree is not used to eliminate loops, you should ensure a loop-free topology
below the Fabric Extender host interfaces.
You can enable host interfaces to accept Cisco Discovery Protocol (CDP) packets. This protocol only works
when it is enabled for both ends of a link.
CDP is not supported on fabric interfaces when the Fabric Extender is configured in a virtual port channel
(vPC) topology.
Note
Ingress and egress packet counters are provided on each host interface.
For more information about BPDU Guard, see
Understanding BPDU Guard, on page 94
.
Host Port Channel
The following fabric extenders support port channel host interface configurations. Up to eight interfaces can
be combined in a port channel. The port channel can be configured with or without Link Aggregation Control
Protocol (LACP).
•
Cisco Nexus 2248TP
•
Cisco Nexus 2348UPQ
•
Cisco Nexus 2348TQ
•
Cisco Nexus 2232PP
•
Cisco Nexus 2332TQ
•
Cisco Nexus 2224TP
•
Cisco Nexus 2248PQ
•
Cisco Nexus B22 Fabric Extender for Fujitsu (N2K-B22FTS-P)
•
Cisco Nexus B22 Fabric Extender for Dell (N2K-B22DELL-P)
•
Cisco Nexus B22 Fabric Extender for HP (N2K-B22HP-P)
Cisco Nexus 6000 Series NX-OS Layer 2 Switching Configuration Guide, Release 7.x
150
Configuring the Fabric Extender
Layer 2 Host Interfaces