What methods are used to start and configure services in the Ubuntu operating system?

In Ubuntu, systemd is usually used to manage services.

Main commands:

• systemctl start <service> — start a service.
• systemctl stop <service> — stop a service.
• systemctl restart <service> — restart a service.
• systemctl enable <service> — enable auto-start on boot.
• systemctl disable <service> — disable auto-start.
• systemctl status <service> — check service status.

To configure services, edit their unit files, usually located in /etc/systemd/system/ or /lib/systemd/system/.

Example to start and enable nginx:

sudo systemctl start nginx
sudo systemctl enable nginx
sudo systemctl status nginx

Earlier, Ubuntu used Upstart or init.d scripts, but now systemd is standard.