AZ-500 Microsoft Azure Security Technologies Exam

Architect and Tune Azure WAF Solutions

The Azure Web Application Firewall (WAF) is a service that protects web apps from attacks such as SQL injection and cross-site scripting. When planning a WAF, you must analyze network topology and traffic patterns to pick the right hosting model—Application Gateway, Front Door, or a CDN. The Application Gateway WAF provides regional, dedicated protection, while Front Door WAF offers global edge security closer to users. It is important to evaluate latency and throughput needs to ensure reliable defense.

Managed rule sets like OWASP provide prebuilt protections against common web exploits, and custom rules enable scenarios such as rate limiting or geo-filtering. You can configure bot mitigation and IP restriction to block unwanted traffic or malicious addresses. Key configuration areas include:

• OWASP baseline for general threat detection
• Custom rule sets for application-specific patterns
• Rate limiting to prevent denial-of-service floods
• Geo-filtering to restrict access by region
  These rules help you fine-tune your firewall to reduce false positives.

When you deploy a WAF policy, you choose Detection mode to monitor traffic or Prevention mode to block threats in real time. It is smart to start in Detection mode to avoid false positives and gather data on legitimate traffic. After reviewing logs, you adjust rule thresholds or add exclusions and then switch to Prevention mode for enforcement. Policy changes typically propagate within 20 minutes on Front Door edges and regionally on Application Gateway, so plan updates accordingly.

Choosing the right WAF SKU is essential for capacity planning and performance. Application Gateway WAF V2 and Front Door Premium SKUs offer autoscaling throughput and TLS offloading for encrypted traffic inspection. Evaluate your expected request volume and connection rates to avoid bottlenecks that could slow down applications. In some cases, using a CDN with WAF can improve static content delivery while applying the same rule sets at the edge.

Effective tuning relies on diagnostic logs and metrics streamed to Azure Monitor, Log Analytics, or Event Hubs. By analyzing WAF logs, you identify false positives, adjust rules, and create exclusions in an iterative process. You can set up alerts on key metrics like blocked requests or rule match rates for real-time incident response. Continuous monitoring ensures your WAF policy stays optimally tuned against evolving threats.

Conclusion

In summary, planning and implementing an Azure WAF involves selecting the right hosting model, configuring managed and custom rules, and choosing the proper deployment mode. You must also pick a suitable SKU and plan for capacity to ensure consistent performance. Finally, ongoing tuning based on logs and metrics is important for keeping protections up-to-date. Mastering these steps helps safeguard web applications from a wide range of attacks.