What happens if you esx server stops reporting its memory and cpu usage? What if you cannot connect to any VM’s? I just ran into this issue today. What you need to do is restart the vmware-mgmt service on the ESX Console.
What you will need to do is connect to the ESX Service console via Putty, once there login as a user who has root access, then type su – and hit enter, now put in the root username and password. Once you are connected as the root user, type this in “service mgmt-vmware restart” This will restart the Vmware Virtual Center Management Agent and allow you to gain back control of your ESX Server.