There is several ways to restart ESXi server. You can do it from the console or from the VI client. It's pretty straightforward. Sometimes restarting the management agents of ESXi is sufficient. How-to restart ESX or ESXi server? Simple and easy. For the console access you have to have an access to the server room however or remotely via ILO, DRAK or iPMI. Also you'll need the root password to be able to connect to your ESXi host.
Here are the different procedures for each case.
Restarting ESXi from the Console of the Server (DCUI):
To restart ESX Server 3i from the console of the server:
2.) Connect to the Console of your ESX 3i Server.
3.) Press F12.
4.) Enter the root user name and password when prompted.
5.) Press F11 to restart the system.
Restarting ESXi from the VI client interface:
1.) Ensure all virtual machines are powered off. Or if you have a VMotion, moved to another host.
2.) Right-click on the ESX Server host from the Inventory and click Enter Maintenance Mode.
3.) When complete, right-click on the ESX Server host in the Inventory and click Reboot.
4.) Enter a reason (if you want) in the reboot server window.
5.) Click OK.
6.) When ESX host restarts, then right-click on the ESX Server from the Inventory and click Exit Maintenance Mode.
You can restart ESXi from the DCUI (direct console user interface)
- login to the DCUI as root
- use the Up and Down arrow to navigate to restart the management agents
- Go to Troubleshooting options > Restart the management agents
- Press enter followed F11 to restart the services
- Press enter again than press Escape to log out off the system
Check the video from VMware: