I changed the network settings, but I made a mistake. As a result, I can’t access the web GUI.
Additionally, I have GPU pass-through enabled, and the GPU driver is in the blacklist, resulting in no video output.
In this case I am not able to connect to the host using ssh or webUI.
Solution:
- Boot into your bootloader (mostly 
gruborsystemd-boot, select your preferred kernel but do not press enter. - Press e to go into edit mode.
 - Depending on the boot-loader go to the kernel-commandline entry:
- For 
grub: scroll down to thekernelline you will boot from, it starts withlinux /vmlinuz-... - For 
systemd-bootthe kernel commandline is directly editable 
 - For 
 - Scroll to the end of that line, optionally remove the 
quietin the line and appendinit=/bin/bash - For 
grubpressCtrl Xto boot, forsystemd-bootsimply press Enter 
In the resulting shell:
# Remount / as Read/Write
mount -o remount,rw /
cd /etc/network/
vi interfaces
Done. Enjoy!
