Linux – Why X server runs on TTY1 and not TTY7 on Arch Linux

In 4.13, +CONFIG_PEAQ_WMI=m was added to the vanilla kernel, a dependency of CONFIG_INPUT_POLLDEV. This has resulted in regressions for various types of systems, including the console spamming you experienced. It appears to have been introduced with this commit.

Blacklisting input_polldev is the current workaround.

The DefaultInstance refers to systemd instances of a service not which one should be parent. On many Linux distros including Debian inittab is still what spawns ttys. The service file is there more or less to keep track of it.

Usually the display manager decides the starting tty and spawns one on tty7 or above then switches to it much like chvt. Since you aren't using one xinit DOES NOT spawn a new tty it will only open X on the current TTY. Note that X is usually using tty7 not tty6. You should refer to the Arch Linux wiki here: https://wiki.archlinux.org/index.php/Xinit on how to use xinit.

So your choices are:

• Use a Window Manager
• Use multi seat
• auto login

To put this another way your window manager is what handles session authentication. Without it you rely on the tty as logined in for this purpose. So switching to another requires it also be logged in which case you'd have to switch to it and login anyway (or use autologin) Thats why the display manager is what asks for your login credentials.

Given your setup the proper way would be, you can't switch ttys unless they auto login because startx is tied to the tty unless you reauthenticate which is what a window manager does.