If you are running your ESX or ESXi management console on DHCP and need to force a DHCP lease renewal, here is how it can be done in both ESX and ESXi.
ESX: Run the following two commands locally in the service console (COS):
ifdown vswif0
ifup vswif0
ESXi: Use the local console menu to “Restart Management Network”:
If you can run ‘screen’ at the console you might be able to get away with:
ifdown vswif0 ; ifup vswif0
‘nohup’ (if available) can do that as well, but it is a pain to use.