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Sharon
Sharon

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Mastering Web Server Security on Linux with SafeLine WAF

#cybersecurity #safeline #waf #devops

When you’re running a Linux web server, security isn’t optional — it’s mission-critical.

Sure, there are plenty of free, open-source WAFs (Web Application Firewalls) out there, but many come with steep learning curves and endless configuration hurdles.

For my small personal project, I needed something free, lightweight, and easy to deploy. After digging around, I found SafeLine WAF by Chaitin Technology — and it turned out to be exactly what I was looking for.

How SafeLine WAF Fits In

Before SafeLine, my stack was simple:

User → Apache → Server
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Now, with SafeLine in place, it looks like this:

User → SafeLine WAF → Apache → Server
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This extra layer stops malicious traffic before it even reaches Apache.

Setup adjustments:

  • Port changes: Move your web server from port 80 to 81, letting SafeLine handle HTTP on 80.
  • HTTPS configuration: Make sure port 443 is set up for encrypted traffic.

Redirecting HTTP to HTTPS

Enforcing HTTPS is one of the simplest but most effective ways to secure your site.

SafeLine makes it easy — you just tweak its built-in Nginx configuration.

  1. Open the custom parameters file: 
   safeline/resources/nginx/custom_params
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  1. Add the redirect rule: 
   return 307 https://www.waf.com$request_uri;
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  1. Restart the SafeLine Nginx service: 
   docker exec safeline-tengine nginx -t
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What Else Can SafeLine Do?

Beyond basic traffic filtering, SafeLine includes some surprisingly useful features for a free, open-source tool:

  • Maintenance mode
  • IP blacklist/whitelist
  • CAPTCHA challenge

Common Installation Pitfalls

If you hit issues during installation, here are two I ran into:

1. Directory already exists

rm -rf /data/safeline
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2. Network errors
Check existing Docker networks:

docker network ls
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Remove invalid ones:

docker network rm <network_id>
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Final Thoughts

If you’re looking for a free, powerful, and beginner-friendly WAF for Linux-based web servers, SafeLine WAF deserves a spot at the top of your list.

It’s fast to deploy, easy to manage, and comes packed with features — all without locking you into a paid plan.

Join the SafeLine Community

If you continue to experience issues, feel free to contact SafeLine support for further assistance.

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