How to Keep Linux Scripts Running After Logout Without systemd

Background

When developing scripts on Linux it is often necessary to keep a process running after the user logs out, without relying on systemd or other heavyweight init systems.

Using nohup

nohup

runs a command immune to the SIGHUP signal. By default the command’s standard output and error are written to nohup.out, but the output can be redirected.

nohup ./my_script.sh &

nohup ./my_script.sh > my_script.log 2>&1 &

Using disown

disown

removes a background job from the shell’s job table, preventing it from receiving SIGHUP on logout.

./my_script.sh &
 disown

It can be combined with nohup for extra safety:

nohup ./my_script.sh &
 disown

Using setsid

setsid

creates a new session and runs the program inside it, fully detaching the process from the controlling terminal.

setsid ./my_script.sh &

Using tmux

tmux

is a terminal multiplexer that can create a detached session, run a command inside it, and later re‑attach.

tmux new-session -d -s my_session './my_script.sh'

Re‑attach when needed:

tmux attach-session -t my_session

Using screen

screen

provides similar functionality to tmux. screen -dmS my_session ./my_script.sh Re‑attach later:

screen -r my_session

Using at

The at utility schedules a one‑time job. Ensure the atd daemon is running, then submit the script for immediate execution.

sudo systemctl start atd

echo "./my_script.sh" | at now

Comparison of tmux and screen

Session management : Both allow creation, detachment, and re‑attachment of sessions.

Window/pane splitting : tmux supports multiple panes within a single window, useful for parallel tasks.

Script friendliness : tmux offers richer command‑line options for automation.

Stability and community : screen is older and widely deployed; tmux has a more active development community and more configurable defaults.

Recommendation

All the methods above keep a script alive after logout. For ad‑hoc or one‑off tasks, nohup, disown, or setsid are sufficient. For long‑running or interactive workloads, a terminal multiplexer is preferable; tmux is generally recommended because of its modern feature set, flexible configuration, and active support, while screen remains a solid fallback.