UCS server ESXi fail to bootup

[Chi Fai Leung]

My UCS server suddently cannot access the ESXi. After reboot, that showed the below screen. Any idea?

[Kirk J]

That is the default UEFI shell you can land at if the system does not detect a valid boot device.

Where was ESXi previously installed?  SD card? Raid drive/VD?

If you hit F6 (boot menu) what options does it show?

Kirk...