Testing and Validating Firewall Rules

Before deploying firewall rules to production, thorough testing ensures they work as intended without disrupting legitimate traffic. A systematic testing approach prevents both security gaps and service outages.

Start with basic connectivity tests:

# Test HTTP access
curl -I http://web_server_ip

# Test HTTPS access  
curl -I https://web_server_ip

# Test blocked ports (should fail)
telnet web_server_ip 22

Verify rate limiting effectiveness:

# Generate traffic to trigger rate limits
for i in {1..200}; do curl http://web_server_ip & done

# Check if rate limiting activates

Test geographic and IP reputation filters:

# Use VPN or proxy to test from different locations
# Verify blocked regions cannot access
# Confirm allowed regions have normal access