Positioning Wafs
Positioning wafs means placing a web firewall directly in front of your public web apps. You set up DNS or load balancers to route all incoming web traffic through this filter first. Most teams place these firewalls at the network edge to block bad requests early. Still, edge rules do not control what logged-in engineers do when they query backend databases directly. Core architectural patterns for positioning wafs Teams choose from three main places when positioning wafs in a network stack.
Wafs: the complete guide
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Positioning wafs means placing a web firewall directly in front of your public web apps. You set up DNS or load balancers to route all incoming web traffic through this filter first. Most teams place these firewalls at the network edge to block bad requests early. Still, edge rules do not control what logged-in engineers do when they query backend databases directly.
Core architectural patterns for positioning wafs
Teams choose from three main places when positioning wafs in a network stack. The first option is the public cloud edge, often linked with a content delivery network. DNS routes user requests to the edge firewall before traffic ever reaches your cloud network. This setup absorbs large traffic spikes and stops common web exploits far from your servers.
The second option sits inside your virtual private cloud right on the app load balancer. Traffic enters your cloud network first, and the load balancer checks each request against firewall rules. The third option places the firewall right beside the app server or inside a cluster ingress controller. Each spot trades broad perimeter protection for deeper context about the specific target app.
To make this work, teams must lock down network routes so traffic cannot skip the firewall. You set up security groups or network rules on your app servers to accept traffic from the firewall only. You also load TLS keys onto the firewall node so it can read encrypted web requests. Without TLS keys, the firewall sees scrambled bytes and cannot inspect headers or request bodies.
Why edge firewalls miss internal data risks
A web firewall excels at scanning untrusted HTTP traffic from public users on the internet. It checks incoming packets against known attack signatures and rate limits aggressive bots. When an external attacker sends a malformed web payload, the firewall drops the request right away.
Still, a web firewall only watches the front door of your public web app. It does not sit in the path when developers or support staff connect to backend systems. Engineers do not run database maintenance or server fixes through a public web form. They use direct database clients, command line tools, and internal scripts over private network paths.
Wafs: architecture patterns and best practices
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Edge setups and network roles only decide who can reach a server or log in. They do not inspect what individual SQL statements or shell commands do once a session starts. If an engineer runs a broad query, the database returns raw emails, phone numbers, or card numbers. A web firewall at the edge never sees this internal traffic and cannot rewrite sensitive fields in results.
How to validate your firewall placement
Before turning on blocking rules, teams must test their network routing and rule accuracy. Start by running the firewall in log-only mode for all incoming production web traffic. Check the logs to make sure legitimate app payloads do not trigger false blocks.
Next, try to send a request directly to the origin server IP address from outside. If the server responds, your network rules are too loose and attackers can skip the firewall. Lock down the origin server firewall so only the web firewall IP range can send traffic. Finally, review your internal data paths and add controls for direct engineer sessions to backend data stores.
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 sits inline in the wire protocol beside those services as an open-source proxy, a sidecar for your Postgres or API. On every query an AI agent or engineer runs against production, hoop.dev decides to pass, mask, block, or hold it for human review.
Your login details and client tools stay as they are while hoop.dev guardrails refuse bad deletes or drops before they run, and hoop.dev data masking rewrites matched sensitive values in responses 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 sit before or after a load balancer?
Most teams place the firewall before the load balancer or attach it directly to the load balancer. Placing it in front stops bad traffic before it consumes load balancer resources.
How do you stop attackers from bypassing a cloud WAF?
You must configure origin server network rules to allow traffic only from the firewall IP addresses. You can also check a secret custom header between the edge node and your origin.
Does a WAF protect direct database sessions?
No, a web firewall only inspects HTTP and HTTPS web traffic directed at web servers. It does not inspect direct database protocols, shell sessions, or internal admin tools.