Apache Web Server Optimization Checklist

1. Basic Configuration Optimization

Update Apache to the latest stable version
Remove unused modules to reduce memory footprint
Tip: Use apache2ctl -M to list loaded modules
Enable the event MPM (Multi-Processing Module) for better concurrency
Tip: Edit /etc/apache2/mods-available/mpm_event.conf
Optimize KeepAlive settings
- Set KeepAlive On
- Adjust KeepAliveTimeout (typically 2-5 seconds)
- Set appropriate MaxKeepAliveRequests

2. Performance Tuning

Adjust TimeOut directive (typically 30-60 seconds)
Optimize MaxRequestWorkers based on available RAM
Set appropriate ServerLimit and MaxConnectionsPerChild
Enable and configure mod_cache for caching static content
Use mod_expires to set appropriate expiration headers
Enable Gzip compression using mod_deflate
Tip: Add AddOutputFilterByType DEFLATE directive for content types

3. Security Enhancements

Disable directory listing (Options -Indexes)
Hide Apache version information (ServerTokens Prod and ServerSignature Off)
Implement ModSecurity Web Application Firewall (WAF)
Use mod_evasive to prevent DoS attacks
Configure SSL/TLS for HTTPS (if not already done)
- Use strong cipher suites
- Enable HSTS (HTTP Strict Transport Security)

4. Logging and Monitoring

Configure log rotation to prevent disk space issues
Set up log analysis tools (e.g., AWStats, GoAccess)
Implement server monitoring (e.g., Nagios, Zabbix, Monit)
Enable mod_status for real-time server statistics
Tip: Restrict access to status page for security

5. File System and OS Tuning

Use noatime mount option for the file system containing web files
Increase open file limits (ulimit) for the Apache process
Optimize kernel parameters for high concurrency
- Increase max file descriptors: fs.file-max
- Tune network settings: net.ipv4.tcp_fin_timeout, net.ipv4.tcp_keepalive_time

6. Content Optimization

Minify CSS, JavaScript, and HTML
Optimize images (compress, use appropriate formats)
Implement a Content Delivery Network (CDN) for static assets
Use browser caching effectively (set appropriate Cache-Control headers)

7. Testing and Benchmarking

Use ApacheBench (ab) for basic performance testing
Implement more advanced load testing tools (e.g., JMeter, Gatling)
Monitor server resource usage during tests (CPU, memory, I/O)
Analyze and optimize based on test results

Note: This checklist provides general guidelines for Apache optimization. The specific settings and optimizations may vary depending on your server hardware, traffic patterns, and specific use case. Always test changes in a staging environment before applying to production.