Cisco Nexus 1000V User Manual

CHAPTER
12-1
Cisco Nexus 1000V Troubleshooting Guide, Release 5.2(1)SV3(1.1)
OL-31593-01
12
Layer 2 Switching
This chapter describes how to identify and resolve problems that relate to Layer 2 switching and includes
the following sections:
• Information About Layer 2 Ethernet Switching, page 12-1
• Port Model, page 12-1
• Layer 2 Switching Problems, page 12-4
• Layer 2 Switching Troubleshooting Commands, page 12-7
• Troubleshooting Microsoft NLB Unicast Mode, page 12-12
• Troubleshooting BPDU Guard, page 12-14
Information About Layer 2 Ethernet Switching
The Cisco Nexus1000V is a distributed Layer 2 virtual switch that extends across many virtualized hosts.
It consists of two components:
• The Virtual Supervisor Module (VSM), which is also known as the control plane (CP). The VSM
acts as the supervisor and contains the Cisco CLI, configuration, and high-level features.
• The Virtual Ethernet Module (VEM), which is also known as the data plane (DP). The VEM acts as
a line card and runs in each virtualized server to handle packet forwarding and other localized
functions.
Port Model
This section includes the following topics:
• Viewing Ports from the VEM, page 12-2
• Viewing Ports from the VSM, page 12-3

Cisco Nexus 1000V Specifications

General

Type	Virtual Switch
Manageable	Yes
NetFlow	Yes
SPAN	Yes
ERSPAN	Yes
Operating System	Cisco NX-OS
Form Factor	Virtual
Hypervisor Support	VMware ESXi
Features	VXLAN
Security Features	Port Security, Private VLANs, ACLs