You shouldn’t have to reboot your ESX servers very often. But when you do, you might want the virtual machines to start up automatically. To configure a virtual machine to start up (or shut down) automatically select the host and click on the Configuration tab. Then click on virtual machine Startup/Shutdown and click on Properties, selecting “Allow virtual machines to start and stop automatically with the system”. As I mentioned in a previous article, you can also configure the operating system to start after a brief delay by providing a Default Startup Delay time, allowing time for booting systems to run scripts or to throw them into Safe Mode. You can also configure automated shutdown options at this screen as well. Also use the Move Up and Move Down options to indicate what order virtual machines start when the system starts. Click Save and the configs are written to the system.
Sometimes you need to boot a system into Safe Mode. But with a virtual machine you don’t have enough time to put a Windows system into Safe Mode. To put a normal system into safe mode, you can just hit the F8 key when Windows is booting. But with a virtual machine the BIOS screen is by default set to go away in 0 settings. Therefore, you need to add a boot delay to mimic a physical host. To get a virtual machine in ESX to have such a boot delay, view all the virtual machines and then right click on the virtual machine you need to configure a delay for. Next, click on Edit Settings and then click on Option. In the options screen, click on Options and then Boot Options. At the Boot Options screen, set the Power-on Boot Delay to 5000ms, which will give you a 5 second delay. Given that 5 second delay you will be able to click on a booting virtual machine and then press the F8 key. From here, open the console window for the virtual machine and start the boot process.
For computers with one operating system installed, you can boot into safe mode, which Windows with a limited set of files and drivers and disables startup programs. This is pretty helpful when troubleshooting Windows problems. To start into safe mode, hold the F8 key down while rebooting a Windows computer. If you see the Windows logo appears, reboot and try again. This should load the Advanced Boot Options screen. Here, use the arrow keys to highlight safe mode option and then Enter. That’s it. Hope this helps!