Waf Placement
You set up waf placement by putting the firewall between web users and your app. Most teams place it right in front of the main load balancer. This setup blocks bad web traffic before it reaches your backend servers. Still, perimeter firewalls cannot see what happens after an internal user logs in. If internal roles are too broad, users can still run unsafe backend commands. How waf placement works in network design A web firewall checks incoming HTTP traffic for common attack patterns. Your
AWS WAF: the complete guide
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You set up waf placement by putting the firewall between web users and your app. Most teams place it right in front of the main load balancer. This setup blocks bad web traffic before it reaches your backend servers. Still, perimeter firewalls cannot see what happens after an internal user logs in. If internal roles are too broad, users can still run unsafe backend commands.
How waf placement works in network design
A web firewall checks incoming HTTP traffic for common attack patterns. Your network routing decides which packets pass through this inspection engine. Most teams choose between three common locations in their network path.
First, you can put the firewall at the DNS edge. Public traffic hits the cloud provider network before it reaches your servers. The edge filters out bad requests and sends clean traffic to your origin. You must lock down your origin IP so attackers enforces policy on the edge.
Second, you can attach the firewall to your cloud load balancer. Traffic enters your virtual network and stops at the load balancer first. The load balancer runs the firewall rules and forwards safe requests to your apps. This pattern keeps traffic inspection close to your compute instances.
Third, you can run the firewall inside your app cluster or host. An ingress controller checks every request right before the app container reads it. This approach lets app teams manage their own filter rules for each service. Still, it uses more compute power inside your own cluster.
What perimeter firewalls solve and where they fall short
Good firewall placement stops automated bots and external web exploits at the border. It blocks known SQL injection strings and cross-site scripting payloads in public requests. It also absorbs large traffic spikes before they crash your web servers.
Still, a web firewall only inspects public HTTP traffic from outside the network. It does not watch direct database sessions or internal admin tools. Engineers and support staff often bypass the web tier to fix production issues. They log in directly to databases, cloud consoles, and internal APIs.
AWS WAF: architecture patterns and best practices
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Once an engineer logs in, the perimeter firewall has no role in the session. It cannot check what specific SQL queries or shell commands the user runs. It also cannot rewrite sensitive fields like emails, phone numbers, or card numbers. If an account has broad permissions, one mistake can delete critical production tables. Protecting the web edge is only half of the security puzzle. Teams also need visibility and control over internal data and system sessions.
Choosing the right location for your team
Start by mapping where your public apps run and how traffic reaches them. If you run static sites and public APIs, edge placement works well. It drops junk traffic far away from your core network.
If you run private internal web tools, place the firewall on an internal load balancer. This checks traffic moving between different network zones inside your cloud account. Always test new firewall rules in count mode before you block live traffic. False positives can break valid API calls and lock out real users. Review your match logs every week to tune noisy rules and spot new trends.
Check database and API queries on the wire
Identity tools, roles, and network rules decide who opens a session. Setup alone cannot check what each query does or mask sensitive values in a response once a session starts. When workflows touch Postgres, MySQL, SQL Server, MongoDB, ClickHouse, Kubernetes APIs, SSH, or internal HTTP APIs, hoop.dev runs beside those services as an open-source proxy, a sidecar for your Postgres or API. It inspects requests coming in and results going back on the wire.
Your login details and client tools stay as they are while hoop.dev guardrails refuse bad deletes or drops before they run. On responses, hoop.dev data masking rewrites matched sensitive values in memory. Furthermore, hoop.dev holds SOC 2 Type II, is MIT licensed, and writes every query and decision to an audit trail that generates evidence for HIPAA, GDPR, and PCI DSS. See the source on GitHub.
Frequently asked questions
Should a WAF go before or after the load balancer?
In most cloud setups, the firewall attaches directly to the load balancer itself. If you use a separate edge vendor, place it before your load balancer.
How do attackers bypass an edge web firewall?
Attackers scan public IP ranges to find your origin server address. Lock your origin firewall so it only accepts traffic from your edge provider.
Does a web firewall protect direct database sessions?
No, a web firewall only inspects HTTP and HTTPS web traffic. It cannot read native database protocols or SSH commands from internal engineers.