I have Ubuntu 16.04.04 LTS server. I was doing some work in
tty1 and then took a lunch break. In the meantime, my desktop monitor went asleep. When I came back, I pressed Esc and my screen awoke and I was at the
tty1 prompt, exactly where I left off. However, when I began typing, I noticed that the characters I entered were not displaying at the prompt. It was as if the keyboard was not working, but I could see that the pre-existing text on the screen would flicker with each key press I made. So, I think (A) the physical keyboard connection is not the issue and (B) the key presses are registering somewhere because of the brief flicker.
Just to double-check, I pressed CtrlAltF2 to go to
tty2 and I began typing (username & password) and the characters I was pressing on the keyboard were displaying as they should. So, my keyboard seemed to work fine in
tty2 (and in
tty4, and so on).
So, I went back to
tty1 and, again, the key presses were not displaying. No key combination seemed to work in
tty1 except the function keys to go to another terminal.
Because, I could not figure out how make my key presses show up in
tty1, I tried
shutdown, but I could not enter
tty1. So, I went to
tty2 and entered
tty2, the command registered and stated the time the computer would shutdown. When it was time to shutdown, a message displayed stating that (I don't remember the exact wording) there was another process taking place. I tried to CtrlC out of the shutdown, but it was stuck too. So, I went to
tty3 and tried to shutdown there and got stuck again. So, I ultimately pushed the power button on my computer for a few seconds and shut down my computer the ugly way. When the computer started back up, the problem was gone and everything seemed to work normally.
What was going on with key presses not displaying (but making the screen flicker) in
tty1? Eager to understand this.