When accessing the ESXi shell via the DCUI with keyboard shortcut ALT+F1 a blank screen with no shell prompt is observed.
VMware ESXi
Disabled ESX Shell
Issue with out of band management console window
Ensure that your ESX Shell is enabled in the DCUI:
Navigate to Troubleshooting: Scroll down to Troubleshooting Options and press Enter.
Enable Shell: Select Enable ESXi Shell.
If your shell is enabled and you continue to see this issue please contact your hardware vendor.