What logs are displayed on a headless setup?

For a project I am working on, I removed the default desktop environment and installed xfce4/xrdp so I can access it remotely. Any dispay is disabled by set-default multi-user.target. All of this is working as I want it, so no issues here.

In this case, when I connect an hmdi screen to my board (devkit carrier) I get a tty1 terminal waiting for me to enter my credentials. However sometimes some logging is output in this screen as well. It is formated as kernel logging like you’d expect form dmesg for examble. Yet, very very little is output here, far from all of what dmesg as to offer.

So finaly my question is, what actually is this output, why does it seem like a heavilty filtered version of dmesg?

If I understand your problem correctly, then the answer is yes, those logs are heavily filter version of dmesg because only specific log level will be printed.

Hi @WayneWWW , thanks for your reply.

I was unaware the kernel even had different log levels, I learned today I guess :) Followup question, is there a way for users to change was messages get filtered? To give some context, I would be useful in some of our headless projects that operators could attact a portable hdmi screen to a jetson and read logging statements. I am already able to pipe text into the kernel logs and it shows up in dmesg but I guess it gets filtered before it hits the screen.