How to Use systemctl to Manage Services on Linux

Quick Answer: systemctl start nginx starts a service. systemctl stop nginx stops it. systemctl restart nginx restarts. systemctl enable nginx makes it start on boot. systemctl status nginx shows if it's running and recent logs.

Essential Commands

# Start a service
sudo systemctl start nginx

# Stop a service
sudo systemctl stop nginx

# Restart (stop + start)
sudo systemctl restart nginx

# Reload config without stopping (if supported)
sudo systemctl reload nginx

# Check status
systemctl status nginx

# Enable (start on boot)
sudo systemctl enable nginx

# Disable (don't start on boot)
sudo systemctl disable nginx

# Enable AND start immediately
sudo systemctl enable --now nginx

# Check if running
systemctl is-active nginx

# Check if enabled on boot
systemctl is-enabled nginx

Check Service Status

systemctl status nginx

Output explained:

● nginx.service - A high performance web server
     Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
     Active: active (running) since Mon 2026-04-06 10:00:00 CDT; 2h ago
       Docs: man:nginx(8)
    Process: 1234 ExecStart=/usr/sbin/nginx (code=exited, status=0/SUCCESS)
   Main PID: 1235 (nginx)
      Tasks: 5 (limit: 4915)
     Memory: 12.5M
        CPU: 234ms
     CGroup: /system.slice/nginx.service
             ├─1235 "nginx: master process /usr/sbin/nginx"
             └─1236 "nginx: worker process"

Apr 06 10:00:00 server systemd[1]: Starting A high performance web server...
Apr 06 10:00:00 server systemd[1]: Started A high performance web server.

List Services

# All running services
systemctl list-units --type=service --state=running

# All services (including stopped)
systemctl list-units --type=service

# All failed services
systemctl --failed

# All enabled services (start on boot)
systemctl list-unit-files --type=service --state=enabled

Common Services

# Examples
sudo systemctl restart mysql
sudo systemctl status docker
sudo systemctl enable --now fail2ban
sudo systemctl reload nginx

View Service Logs

# Recent logs for a service
journalctl -u nginx -n 50

# Follow logs (live)
journalctl -u nginx -f

# Logs since last hour
journalctl -u nginx --since "1 hour ago"

# Errors only
journalctl -u nginx -p err

# Logs from current boot
journalctl -u nginx -b

Create Your Own Service

If you have a Node.js app, Python script, or any program you want to run as a service:

Create /etc/systemd/system/myapp.service:

[Unit]
Description=My Application
After=network.target

[Service]
Type=simple
User=www-data
WorkingDirectory=/opt/myapp
ExecStart=/usr/bin/node /opt/myapp/server.js
Restart=on-failure
RestartSec=5
Environment=NODE_ENV=production
Environment=PORT=3000

[Install]
WantedBy=multi-user.target

Then:

sudo systemctl daemon-reload
sudo systemctl enable --now myapp
sudo systemctl status myapp

Troubleshooting

Service Won't Start

# Check what went wrong
systemctl status myapp
journalctl -u myapp -n 30 --no-pager

# Common causes:
# - Wrong ExecStart path
# - Permission denied (wrong User)
# - Port already in use
# - Missing dependencies

Service Keeps Crashing

# Check how many times it restarted
systemctl show myapp -p NRestarts

# Check exit code
systemctl show myapp -p ExecMainStatus

# View the crash logs
journalctl -u myapp --since "10 minutes ago"

Reset a Failed Service

# Clear the failed state
sudo systemctl reset-failed myapp

# Then start it
sudo systemctl start myapp

Reload After Editing Service File

# After editing any .service file
sudo systemctl daemon-reload
sudo systemctl restart myapp

See Also

• systemd Cheat Sheet
• Linux Commands Cheat Sheet
• Linux Log Files Explained
• Nginx Cheat Sheet
• Docker Cheat Sheet