Troubleshooting Nexus 1000V vDS network issues
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Troubleshooting Nexus 1000V vDS network issues


Article ID: 304703


Updated On:


VMware vCenter Server VMware vSphere ESXi


This article provides high level troubleshooting information only and does not provide any detailed resolution steps. For more information on specific network troubleshooting with Cisco Nexus 1000V devices, see Cisco Nexus 1000 Virtual Switch Manager connection to vCenter fails (1013448).

You are experiencing these issues:
  • Nexus 1000v vNetwork Distributed switches (vDS) in vSphere fail to connect to the physical network after installation.


VMware ESXi 4.1.x Installable
VMware ESX 4.0.x
VMware ESXi 4.0.x Embedded
VMware ESXi 4.1.x Embedded
VMware ESXi 4.0.x Installable
VMware vSphere Web Access 4.0.x
VMware ESX 4.1.x


To troubleshoot networking issues with Cisco Nexus 1000V devices:
  • Confirm that the LUNs designated for Virtual Switch Manager (VSM) and Virtual Ethernet Manager (VEM) data components have not been modified.
  • vCenter Server and the VSM / VEM defined resources meet minimum requirements:
    • VEM is running on ESX or ESXi 4.0 hosts.
    • VSM is running on ESX 4.0 hosts or ESX 3.5 hosts using legacy non-vDS only.
    • ESX hosts have at least 4GB available to run the VSM virtual machine with 2GB dedicated memory.
    • One PNIC for the Service Console.
    • One PNIC for the traffic between VSM and VEM and for virtual machine data traffic.
  • VMware Update Manager is configured to include the index to apply all relevant patches for Nexus 1000V. VEM Pro updates available at
  • Software updates for VEM and Nexus have been applied through Update Manager. For more information, see Configuring patch source in vCenter Update Manager for Cisco Nexus 1000V Virtual Ethernet Module (VEM) (1013134).
  • The VSM virtual machine is running:
    • on the same IP subnet as the ESX hosts that it manages.
    • on an ESX host with three E1000 NICs and access to:
      • Control VLAN 260
      • Packet VLAN 261
      • Management VLAN 20
  • VLANs as defined for vCenter do not conflict with Nexus management VLAN IDs 3968 thru 4047 and 4094.
  • VLANs defined on physical switch ports or across two trunked physical switches are configured as per the Nexus Installation Guides for single switch and dual switch implementations.
  • Per the Nexus Installation Guides, determine that:
    • Nexus 1000V software is installed correctly.
    • vCenter plugins for Nexus are applied.
    • License(s) have been correctly applied on the VSM.

For more information on Cisco Nexus 1000V installation, configuration and licensing, see: