The default graphical login manager begin to launch on startup after I have installed Xubuntu-desktop on my Ubuntu server. But I need the startup directly to the terminal. So I have found the way to load it during startup.
Follow these steps:

1. Open file /etc/default/grub with your favorite text editor (example: sudo gedit /etc/default/grub).
2. Find line with parameter GRUB_CMDLINE_LINUX_DEFAULT=”…” (there will be something instead of ellipses).
3. Append “text” word with whitespace after the last word in brackets (example: GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash text”).
4. Update GRUB: sudo update-grub.
5. Reboot your machine.

via: ubuntuguide.net ^[1]