I got Ubuntu server 18.04.1 running on a laptop with a broken display. Obviously, I Used an external monitor for the install
Now when I disconnected the external monitor, the server suspends within seconds.
I tried to prevent that by masking sleep.target, hypernate.taget, suspend.target, and hybrid-sleep.target.
This worked. It does not suspend :-) But... :-( Now it is filling the logs with about messages 100 messages per second that it can not suspend causing one of the cores running 100%. Again only when the monitor is disconnected.
The laptop lid is still open but eventually, I like it to be closed while the server is still running.
Someone suggested the defective display could be sending some malfunctioned messages to the System, So I disconnected its connector from the mainboard.
What am I missing?