$ curl cheat.sh/
# nologin
# Alternative shell that prevents a user from logging in.
# More information: <https://manned.org/nologin.5>.

# Set a user's login shell to `nologin` to prevent the user from logging in:
chsh -s user nologin

# Customize message for users with the login shell of `nologin`:
echo "declined_login_message" > /etc/nologin.txt

$
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