Create systemd unit timers

Problem

Run a script every day at midnight using systemd.

Solution

1. Systemd service file

## File: /etc/systemd/system/run-script.service
[Unit]
Description=Run a script every day at midnight

[Service]
Type=simple
EnvironmentFile=/path/to/environment
ExecStart=/path/to/script.sh

[Install]
WantedBy=multi-user.target

2. Systemd timer file

## File: /etc/systemd/system/run-script.timer
[Unit]
Description=Run a script every day at midnight

[Timer]
OnCalendar=*-*-* 00:00:00
Unit=run-script.service

[Install]
WantedBy=timers.target

3. Reload and start the timer

sudo systemctl daemon-reload
sudo systemctl enable run-script.timer
sudo systemctl enable run-script.service

Explanation

The systemd unit timers are a powerful feature that allows you to schedule tasks to run at specific times or intervals. They are similar to cron jobs but offer more flexibility and control. You can take advantage of systemd's built-in capabilities like logging and monitoring, environment variables, and more.