Prebid Server Troubleshooting: Essential Techniques for Publishers

When programmatic revenue is on the line, publishers can’t afford delays or failures in their header bidding stacks. Prebid Server is a crucial component for scaling auctions, but its complex configurations and integrations can make troubleshooting a real challenge.

This guide breaks down the most effective, publisher-oriented Prebid Server troubleshooting strategies. Whether you’re running Prebid Server directly, via Prebid.js, or through AMP, you’ll learn how to get the actionable insights needed to keep your monetization engine running smoothly.

Getting More Debugging Information from Prebid Server

Visibility into the auction process is critical for isolating errors and understanding suboptimal results. Prebid Server provides several ways to enable detailed debugging, each tailored to different integration scenarios.

Direct Prebid Server Invocation

When sending OpenRTB requests straight to your Prebid Server instance, you can append specific flags to your request payload. Setting the ‘test’ field to 1 marks the auction as a test (bidders treat it as non-billable) and yields verbose debug details. If you need debug information without making the request non-billable, use ‘ext.prebid.debug’:true instead. These options are invaluable for detailed bid analysis without risking unintended spend or disturbing live campaigns.

Debugging with Prebid.js

For publishers integrating via Prebid.js, you have convenient methods to surface more detail in Prebid Server calls. Adding ‘?pbjs_debug=true’ to your URL or using pbjs.setConfig({“debug”:true}) instructs the pbsBidAdapter to set the debug flag, unlocking extra auction-level insights. Need to simulate a test auction for troubleshooting? Configure pbjs with an ortb2 object to set the ‘test’ flag, all within your configuration script. These tools help trace issues without altering your main page flow.

Troubleshooting AMP Integrations

If your inventory is served through AMP, getting debug data is more restricted. AMP requests typically don’t allow debug toggles natively. However, by capturing and replaying the Prebid Server AMP call outside the AMP context and appending ‘&debug=1’, you can retrieve the needed diagnostic details. This approach is especially useful during initial AMP setups or when troubleshooting intermittent fill issues.

Using Stored Responses for Reliable Testing

Often, real bidding data is unpredictable or hard to replicate, making it difficult to test new configurations or troubleshoot edge cases. Prebid Server’s stored responses feature lets you use hand-crafted bid responses for targeted testing—no dependence on live demand.

How Stored Responses Work

As a publisher, you can craft a bid response and store it in Prebid Server’s database. When making an OpenRTB auction request, reference one or more stored response IDs within your imp[].ext.prebid definitions. For any impression with a stored response ID, Prebid Server ignores live bidders and returns the simulated bid data instead. This technique helps test specific creative behavior, pricing thresholds, or line item setups in GAM without having to wait for the right bid to arrive naturally.

Practical Example for Publishers

Imagine you want to test a creative rendering at a precise CPM or validate a complex revenue-sharing setup. Insert a stored response with your target values and configure your test OpenRTB request to use the corresponding IDs. On trigger, Prebid Server returns your fabricated results, letting you validate downstream systems—like GAM targeting, creative fallback logic, or viewability analytics—without relying on external bidders or the unpredictability of real auctions.

Request Logging and Advanced Troubleshooting in PBS-Java

Deeper issues sometimes require direct analysis of incoming HTTP traffic. For publishers using Prebid Server (Java version), admin endpoints allow dynamic toggling of logging verbosity and capture of raw auction requests.

Activating and Accessing Logs

By authenticating with Prebid Server’s admin endpoints, you can set debugging levels for a defined duration and inspect requests as they hit the ‘auction’ endpoint. This capability reveals the full raw payloads, headers, and parameters being sent—ideal for confirming integration accuracy, tracing malformed requests, or collaborating with tech teams to isolate edge-case failures.

What this means for publishers

With flexible debugging, request simulation, and logging controls, publishers get end-to-end visibility into their header bidding flows. These tools improve troubleshooting speed, reduce reliance on buyer support for issue validation, and help ensure stable revenue by minimizing disruptive errors. Robust diagnostics also support streamlined QA when deploying new ad formats, bidders, or integrations.

Practical takeaway

Ad ops and monetization teams should incorporate Prebid Server’s built-in debugging and stored response capabilities into their regular toolkit. Whenever a new partner is onboarded, or a major code/config change is introduced, use debug flags and stored responses to validate the critical path before going live.

PBS-Java users—make sure admin endpoint access is secured and accessible to trusted team members for deep request analysis. And always document repeatable troubleshooting flows for your team. By taking these proactive steps, you’ll minimize auction downtime, speed up integrations, and maximize the efficiency of your revenue operations.