Knowledge

• Verify VM is connected to the correct port group
  To check if a VM is connected to the correct port group you can check if the Vm is connected to the correct port group. Changing the name of a port group when virtual machines are already connected to that port group causes an invalid network configuration for the virtual machines configured to connect to that port group. The connection from virtual network adapters to port groups is made by name, and the name is what is stored in the virtual machine configuration. Changing the name of a port group does not cause a mass reconfiguration of all the virtual machines connected to that port group. Virtual machines that are already powered on continue to function until they are powered off, because their connections to the network are already established. Avoid renaming networks after they are in use. After you rename a port group, you must reconfigure each associated virtual machine by using the service console to reflect the new port group name. To look up the port group name:
  • Select the VM
  • Right Click and select “Edit Settings”
  • Select the network adaptor of your choosing
  • Check if the drop down box shows the correct network adaptor
• Verify port group settings are correct
  To check to port group settings, for example what physical NIC and / or VLAN are being used you need to check the port group settings. To do so (assuming you have a default vSwitch, not a distributed one):
  • Select “Hosts and Clusters” view (Home > Inventory > Hosts and Clusters)
  • Select an ESX host
  • Select the “Configuration” tab
  • Select “Networking”
  • Select the vSwitch that the port group belongs to
    • Check the Upload Adaptors and check speed, duplex and VLAN trunk on the switch
  • Click “Properties” on that port group
    • Select the port group in the pop-up screen that appears and click “Edit”
    • Check if the VLAN mentioned is the correct one.
• Verify that the network adaptor is connected within the VM
  To check is the NIC is connected (virtually connected) check the VM properties:
  • Select the VM
  • Right Click and select “Edit Settings”
  • Select the network adaptor
    • Check if the box “Connected” is ticked under “Device Status”
    • Check if the box “Connected at power on” is ticked (optional)
• Verify VM network adaptor settings
  The Virtual NIC has some settings on its own. To check:
  • Select the VM
  • Right Click and select “Edit Settings”
  • Select the network adaptor
    • Check if the adaptor is of the correct type (e1000, enhanched VMXNET3 etc.)
    • Check if the adaptor has the correct MAC address (or better; auto)
• Verify physical network adaptor settings
  All virtual NICs are connected through physical adaptors. Those adaptors, again, have specific settings on their own. To check those:
  • Select “Hosts and Custer's” view (Home > Inventory > Hosts and Custer's)
  • Select an ESX host
  • Select the “Configuration” tab
  • Select “Networking”
  • Select the tab “Network Adaptors”
  • Check “Edit” to change the speed and duplex
• Verify vSphere network management settings
  Network Management of management network??? If you know the answer? Drop my a line or use the comment system please.

Tools

• ESX/ESXi Configuration Guides
  
• Product Documentation
• vSphere Client
• ping, vmkping, tcpdump, nslookup