I think there are 2 levels of GUI-less-ness in virtualization software like VirtualBox.
Today I want to write about 1st level of GUIless-ness in VBox.
One can use VBoxManage CLI tool or open source Web app to modify/start/stop VBox guests.
After starting up VBox guest, one can attach to guest's console remotely by using RDP tool like WIndows OS's
But......., you may ask, what about if I goofed when modifying grub.conf and guest doesn't boot with default
GRUB entry? Can I attach to guest's console before grub selection screen times out?
One way to achieve this is to make BIOS screen timeout longer like:
$ VBoxManage modifyvm "OracleSolaris11_1" --bioslogodisplaytime 60000
Now, if you attach within 60 seconds , you will get this screen.
Now, if you hit F12 , you will get this. You don't do this when you edited grub.conf wrongly but I hope you get the idea.
My "Remote Desktop"'s title bar says it's localhost:3390 but it's actually tunneled to remote Solaris server. :)