If ESXi console does not respond at all after logging in or you Unable to restart the management agents on ESX host. Press ALT F1 to get to the command line. and run following command to restart the management network or
If you are logging via SSH (putty) etc.
/sbin/services.sh restart (This will only work with ESXi)
For ESX host use following
service mgmt-vmware restart
To restart the management agents on ESXi:
Connect to the console of your ESXi host.
Press F2 to customize the system.
Login as root.
Using the Up/Down arrows navigate to Restart Management Agents.
Note: In ESXi 4.1 and ESXi 5.0, this option is available under Troubleshooting Options.
Press F11 to restart the services.
When the service has been restarted, press Enter.
Press Esc to logout of the system.