vCenter Server events display the message: Lost network connectivity on DVPort

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• In the vCenter Server events, you see messages similar to:
  
  Lost network connectivity on DVPorts: "1166/9c f1 3e 50 3e ## ## ##-## ## ## b9 5a 3c ea a1". Physical NIC vmnic2 is down.
  
  
• After seeing the preceding message, you see a message similar to:
  
  Network connectivity restored on DVPorts: "1166/9c f1 3e 50 3e ## ## ##-## ## ## b9 5a 3c ea a1". Physical NIC vmnic2 is up.
  
  
• In the vmkernel or messages log, you also see messages similar to:
  
  Oct 6 10:49:27 host1 vmkernel: 65:23:47:01.182 cpu33:93674)etherswitch: L2Sec_EnforcePortCompliance: client VIRTUALMACHINE.eth0 requested mac address change to 00:00:00:00:00:00 on port 0x200030e, disallowed by vswitch
Oct 6 10:49:27 host1 vmkernel: 65:23:47:01.182 cpu33:93674)etherswitch: L2Sec_EnforcePortCompliance: client VITRUALMACHINE.eth0 has policy vialations on port0x200030e. Port is blocked
  
  
• Immediately following these messages, the port is unblocked per the vmkernel or messages log:
  
  Oct 6 10:49:27 host1 vmkernel: 65:23:47:01.182 cpu33:93674)NetPort: 982: enabled port 0x200030e with mac xx:xx:xx:xx:xx:xx

Cause

These messages are received because the vSwitch or port group security policy "MAC Address Changes" is set to Reject. During virtual machine power-up and vMotion migration, the host may momentarily list the virtual machine's MAC address as 00:00:00:00:00:00 while it is initializing. Immediately, the virtual machine's correct MAC address is displayed and the port is unblocked.

Note: There is no adverse effects on the virtual machine in question.

 

For more information regarding the virtual switch security setting "MAC Address Changes" please refer to: MAC Address Changes

Resolution

These messages can be safely ignored.

Although the messages indicate that one or more vmnics are down, this is only from the virtual machine's perspective and does not indicate that the physical vmnic is down on the host.

Note: The message Uplink redundancy restored on dvPorts: "dvPort1" Physical NIC vmnic1 is up is not similar to the messages listed in the Symptoms section. However, this message indicates that the Physical NIC vmnic1 is up after a down event.

Additional Information

Similar events and log messages can occur for other reasons. For more information, see Uplink redundancy restored on DVPorts events for specific virtual machine Dvports (1032895).