Skip to main content

Service Management: Start, Stop, Control

Services are background processes that run automatically. You need to control them.

Here's the thing: Service management is what you'll do constantly. Start services. Stop services. Check status.

Basic Control​

Start, Stop, Restart​

sudo systemctl start service-name
sudo systemctl stop service-name
sudo systemctl restart service-name

Real examples:

sudo systemctl start nginx
sudo systemctl stop nginx
sudo systemctl restart nginx

My take: These are the commands you'll use most. Learn them.

Reload vs Restart​

sudo systemctl reload service-name    # Reload config
sudo systemctl restart service-name   # Stop and start

The difference: Reload re-reads config without stopping. Restart stops and starts.

When to use: Reload if service supports it (nginx does). Restart if it doesn't.

My take: Try reload first. It's faster. No downtime. Restart if reload doesn't work.

Enable and Disable​

sudo systemctl enable service-name    # Start at boot
sudo systemctl disable service-name   # Don't start at boot

Enable = Start automatically when system boots.

Disable = Don't start automatically.

Real example:

sudo systemctl enable nginx           # Start nginx on boot
sudo systemctl disable nginx          # Don't start on boot

My take: Enable services you want running. Disable services you don't need.

Check Status​

systemctl status service-name

Output shows:

  • Loaded = Service file loaded
  • Active = Is it running? (active, inactive, failed)
  • Main PID = Process ID
  • Logs = Recent log entries

What matters: Active: active (running) = Good. Active: failed = Bad.

My take: status shows everything. Use it to see what's happening.

List Services​

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

My take: list-units --failed is useful. Shows what's broken.

Common Services​

sudo systemctl start nginx
sudo systemctl start apache2
sudo systemctl start mysql
sudo systemctl start docker
sudo systemctl start ssh

These are the services you'll actually manage. Web servers. Databases. Docker. SSH.

Troubleshooting​

Service Won't Start​

systemctl status service-name        # Check status
journalctl -u service-name          # Check logs

My take: Check status first. Then check logs. Logs tell you why.

Service Failed​

systemctl status service-name        # See error
sudo systemctl restart service-name  # Try restart
journalctl -u service-name -n 50     # Recent logs

My take: Failed services need fixing. Check logs. Fix the problem.

Common Patterns​

Start and Enable​

sudo systemctl start nginx
sudo systemctl enable nginx

Check if Running​

systemctl is-active nginx            # Returns: active or inactive

Reload Config​

sudo systemctl reload nginx          # Reload if supported
sudo systemctl restart nginx          # Restart if not

Common Mistakes (I've Made These)​

  1. Forgetting sudo: Service management needs root. Use sudo.

  2. Using restart instead of reload: Reload is faster. Use it when possible.

  3. Not checking status: Services can fail silently. Check status.

  4. Not enabling services: Services don't start on boot unless enabled. Enable them.

  5. Not checking logs: When services fail, logs tell you why. Check them.

Real-World Examples​

Deploy New Version​

sudo systemctl stop nginx
# Deploy files
sudo systemctl start nginx
sudo systemctl status nginx

Reload Configuration​

# Edit config
sudo vim /etc/nginx/nginx.conf
# Test config
sudo nginx -t
# Reload
sudo systemctl reload nginx

Troubleshoot Service​

systemctl status nginx
journalctl -u nginx -n 100

What's Next?​

Now that you can manage services, you control what runs. Or learn about Networking to connect systems.

Personal note: When I started, I'd restart services for everything. Then I learned reload. Now I reload when possible. It's faster. No downtime. Small things matter.