Keeping your server running after closing SSH: screen and tmux

Everything you start in an SSH session dies when you close the session. To keep your server running, start it inside screen or tmux: they are "terminals that do not close", which you detach from and come back to.

With screen (the simplest)

apt install -y screen

# 1) Open a named session
screen -S minecraft

# 2) Inside it, start your server as usual
cd /home/minecraft/server && java -Xms4G -Xmx4G -jar paper.jar --nogui

• Leave without stopping it: Ctrl + A then D.
• List your sessions: screen -ls
• Back to the console: screen -r minecraft

With tmux

apt install -y tmux
tmux new -s rust

• Leave without stopping it: Ctrl + B then D.
• List your sessions: tmux ls
• Back: tmux attach -t rust

Common mistakes

• Pressing Ctrl + C inside the session stops the server, it does not take you out. To leave without stopping it, use the combination above.
• "There is no screen to be resumed": the session no longer exists, usually because the server closed or the VPS restarted.

It does not come back after a reboot

screen and tmux survive closing SSH, but not a VPS reboot. If you want the server to start by itself when the machine boots and come back up if it crashes, make it a service: how to create a systemd service.