Systemctl has a reputation for being complicated. New Linux users see it everywhere and assume it controls every moving part of the system. The truth is simpler. Systemctl is just the tool that manages background services. Once you learn a few core commands, it becomes predictable and easy to use.
This guide walks through those exact commands, with plain-English explanations and real-world examples you can use immediately. If you want to follow along in your own terminal, the video has a link to spin up a free Linode instance.
Let’s get started.
What Systemctl Actually Does
On Linux, almost everything running in the background is a service.
Web servers, firewalls, SSH, monitoring tools — each one is a service managed by systemd.
Systemctl is the command you use to interact with these services. With it, you can:
• Check whether a service is running
• Start or stop it
• Restart it after a configuration change
• Enable or disable it at boot
• List everything running on the system
This makes systemctl one of the most important tools you’ll use as an admin, developer, or student learning Linux.
1. Check the Status of a Service
systemctl status ssh
This tells you whether the service is active, when it started, and if there are any recent errors.
When to use it
• Someone can’t SSH into a server
• A web app isn’t loading
• You’re troubleshooting something that might be service-related
Always start with status before making any changes.
2. Start a Service
sudo systemctl start ssh
Most systemctl actions require sudo.
If the command returns nothing, that means it worked. Systemctl only reports problems.
When to use it
• A service didn’t start after a reboot
• Maintenance accidentally stopped it
• You’re enabling SSH or Apache for the first time
3. Stop a Service
sudo systemctl stop ssh
Stopping a service cleanly is useful before updates or system changes.
When to use it
• You’re updating a web server
• You need to stop a service that’s using too many resources
• You’re hardening a machine and turning unused services off
4. Restart a Service
sudo systemctl restart ssh
This is the command you’ll use constantly.
If you edit a configuration file, the changes don’t take effect until the service restarts. New admins often forget this and wonder why nothing changed.
When to use it
• You updated sshd_config
• You changed Apache or NGINX configs
• A service is behaving strangely and needs a clean restart
5. Check if a Service Is Running (Simple Output)
systemctl is-active ssh
This returns one word:
• active
• inactive
• failed
Perfect when you just want a straight yes or no.
6. Enable a Service at Boot
sudo systemctl enable ssh
This sets the service to start automatically when the system boots.
When to use it
• After installing a new service
• When you want something always available
• When configuring a fresh server
7. Disable a Service at Boot
sudo systemctl disable ssh
This does not stop the service. It just prevents it from starting automatically.
When to use it
• Hardening a server
• Reducing unnecessary resource usage
• Disabling leftover services you don’t need
8. List All Running Services
systemctl list-units --type=service
This shows everything systemd is managing right now.
When to use it
• Troubleshooting slow boot times
• Checking for strange or unknown services
• Seeing the full picture of what your system is running
Common Beginner Mistakes
1. Forgetting sudo
Most actions require root. If something fails, rerun it with sudo.
2. Restarting the wrong service
Always check systemctl status name first to confirm the exact service name.
3. Thinking enable = start
Enabling only sets the service to start automatically at boot.
It does not start it right now.
You still need start.
A Practical Real-World Workflow
Let’s say you update your SSH configuration.
Here’s the safe and correct workflow:
1. Check the current status
sudo systemctl status ssh
2. Restart the service to apply changes
sudo systemctl restart ssh
3. Confirm it came back clean
systemctl is-active ssh
This is exactly how real sysadmins work.
Once you understand this pattern, systemctl becomes simple.
Bonus: See Which Services Start at Boot
systemctl list-unit-files --type=service
This shows every service on the system and whether it’s enabled.
It’s a great next step for understanding how Linux starts up.
Conclusion
Systemctl looks complicated until someone breaks it down into a handful of core commands. Work through these a few times and you’ll start feeling confident managing services on any Linux system.