I try to build a reproducible automated build environment based on Debian 8.1 Jessie. I created a boot iso image based on a netinstall image and put a preseed.cfg file in int for automatic installation. I managed to get it bootable with BIOS and UEFI and can install a KDE Developer Debian in VMWare Workstation 11 fully automated.
I have also a server iso image to install a debian Server with Jenkins, both with BIOS and UEFI Boot.
But after the installation, the Version with UEFI Boot shows a black Screen when started.
I can blindly log in, start the gui with "startx" and see my installed xfce desktop. When i quit xfce the console is usable and visible.
I tried suggested bootparameters "nomodeset" and "vga=Linux" that i found with google to no avail.
I also tried to debug the boot prozess, to find out which command leads to a blank screen, but i did not find the right place to delay the processes at bootup so i can see when the messages dissapear (quiet bootparameter was removed :-)
I also tried to reset the console to no avail.
Can anybode point me to a tool that does the same "switching" like X so the console is useable?
Can anybody give me some hints how to debug the bootprocess to find out which command is causing this behaviour?
I dont want to install X because this should be a headless server system later.