How to Run Commands Automatically on Linux Boot: rc.local, systemd, init.d, and cron

rc.local Method

The traditional rc.local file runs custom commands near the end of the boot process. Edit /etc/rc.local, make it executable, and add the desired script or commands.

sudo vi /etc/rc.local

#!/bin/bash
# Print welcome message
echo "欢迎回到 Linux 世界！"
# Start custom service
/home/user/myservice start
exit 0

Ensure the file has execute permission and, on systemd‑based distributions, enable the compatibility service:

sudo systemctl enable rc-local

systemd Service Unit

On modern Linux, systemd manages services. Create a unit file that runs a script once at boot.

sudo vi /etc/systemd/system/mybootscript.service

[Unit]
Description=My Boot Script Service
After=network.target

[Service]
Type=oneshot
ExecStart=/home/user/bootscript.sh

[Install]
WantedBy=multi-user.target

Reload the daemon, enable, and start the service. Use journalctl to view logs.

sudo systemctl daemon-reload
sudo systemctl enable mybootscript.service
sudo systemctl start mybootscript.service
sudo journalctl -u mybootscript.service

init.d Script

For SysVinit‑compatible systems, place a script in /etc/init.d with proper header information.

sudo vi /etc/init.d/myinitdscript

#!/bin/bash
# BEGIN INIT INFO
# Provides: myinitdscript
# Required-Start: $remote_fs $syslog
# Default-Start: 2 3 4 5
# Short-Description: My Init.d Script
# Description: This script is used to perform custom tasks during system startup and shutdown.
# END INIT INFO

case "$1" in
  start)
    echo "Starting myinitdscript"
    /home/user/myscript.sh start
    ;;
  stop)
    echo "Stopping myinitdscript"
    /home/user/myscript.sh stop
    ;;
  *)
    echo "Usage: $0 {start|stop}"
    exit 1
    ;;
esac
exit 0

sudo chmod +x /etc/init.d/myinitdscript
sudo update-rc.d myinitdscript defaults

Cron @reboot

Although cron is mainly for periodic tasks, the @reboot directive can run a script at boot. @reboot root /home/user/cleanup.sh Ensure the cron daemon is running:

sudo service cron status
sudo service cron start

Each method has its own advantages: rc.local is simple but may be disabled; systemd offers fine‑grained control and logging; init.d provides compatibility with older SysVinit systems; and cron @reboot is easy to add alongside other scheduled jobs. Choose the approach that best fits your distribution and automation requirements.