I've had a strange issue with an Ubuntu 14.04 server installation recently, and would like some pointers to diagnose the cause of the problem.
The OS will not boot unless a monitor is connected via the VGA port.
I believe that the boot process may be stalled at the grub menu, as the server turn off immediately when the power button is pressed, whereas power off when the OS is running takes a few seconds through the normal ACPI process.
As the OS isn't starting, there are no logs to guide me through a debugging process. What can I do to begin to understand where the problem lies?