I'm trying to make ESXi Shell (or at least DCUI) be available through a serial console. The hardware I'm using is an ASMB7-iKVM management module which supports Serial-over-LAN.
Steps I've taken:
Set VMkernel.Boot.tty1Port to com2
Set VMkernel.Boot.com2_baud to 112500
Reboot the hypervisor
Try to connect via SoL
I'm getting all the output, including the boot log messages and the ESXi Shell prompt, yet ESXi doesn't react to any key presses. Same problem if I redirect output of tty2 (DCUI) instead of tty1 (Shell). SoL works normally when accessing server's BIOS, all keys act as expected.
The server does not meet the criteria of a headless machine, as it has an onboard graphics card and there is no way to force enable "headless mode" in BIOS.