Grub Composite Console
In the past, I’ve described how to get a serial console going on Illumos based systems. If you ever used a serial console in Grub (regardless of the OS you ended up booting), you probably know that telling Grub to output to a serial port causes the VGA console to become totally useless — it’s blank.
Well, if you are using Illumos, you are in luck. About 5 months ago, Joyent integrated a “composite console” in Grub. You can read the full description in the bug report/feature request. The short version is: all grub output can be sent to both the VGA console as well as over a serial port.
It is very easy to configure. In your menu.lst, change the terminal to composite. For example, this comes from my test box’s config file (omitting the uninteresting bits):
serial --unit=0 --speed=115200 terminal composite
Note the use of composite instead of serial. That’s all there is to it.