Overview
CrowdSec is an open-source, community-driven security engine. It detects attacks (brute force, DDoS, scans) by analyzing logs and shares threat intelligence with the community. Think fail2ban but collaborative and modern.
Instructions
Step 1: Install
bash
curl -s https://install.crowdsec.net | sudo bash
sudo apt install crowdsec crowdsec-firewall-bouncer-iptables
Step 2: Configure Collections
bash
# Install detection scenarios
sudo cscli collections install crowdsecurity/nginx
sudo cscli collections install crowdsecurity/sshd
sudo cscli collections install crowdsecurity/linux
sudo cscli collections list
Step 3: Monitor
bash
sudo cscli decisions list # blocked IPs
sudo cscli alerts list # alerts
sudo cscli metrics # statistics
Step 4: Docker Deployment
yaml
# docker-compose.yml — CrowdSec with Nginx bouncer
services:
crowdsec:
image: crowdsecurity/crowdsec
volumes:
- /var/log/nginx:/var/log/nginx:ro
- crowdsec_config:/etc/crowdsec
- crowdsec_data:/var/lib/crowdsec/data
environment:
COLLECTIONS: "crowdsecurity/nginx crowdsecurity/http-cve"
bouncer:
image: crowdsecurity/nginx-bouncer
environment:
CROWDSEC_BOUNCER_API_KEY: your-api-key
volumes:
crowdsec_config:
crowdsec_data:
Guidelines
- Free and open-source. Community shares 10M+ threat signals.
- Bouncers enforce decisions — iptables, nginx, Cloudflare, AWS WAF.
- Lower false positives than fail2ban due to community-validated intelligence.
- Console (app.crowdsec.net) provides dashboard and threat visualization.