What is WAF monitor mode, and why start there?
The biggest fear with any web application firewall isn’t that it will miss an attack. It’s that it will block a real customer: a checkout that fails, a form that won’t submit, a partner’s webhook that gets rejected at 2 a.m.
Monitor mode is how you avoid that.
What monitor mode is
In monitor mode, sometimes called detection-only or log-only mode, the firewall inspects every request exactly as it would in blocking mode, scores it and records what it would have done. Then it lets the request through.
Nothing changes for your visitors. You get a record of every request the firewall would have blocked, with the rule that matched and where in the request it matched.
Why start there
Every application is a bit unusual. A search box where people paste code snippets, a CMS editor that saves HTML, an API that takes JSON with SQL-looking keywords in it: all of these are normal for that app, and any of them can look like an attack to a generic rule.
If you switch a firewall straight to blocking, you find these cases when customers complain. If you start in monitor mode, you find them in a log, before anyone is affected.
Monitor mode also tells you something useful about the attacks themselves. On our own sites, in the 7 days to 7 November 2026, block mode would have stopped 159 clients, and every one we profiled was a scanner or fuzzer. That’s the kind of evidence you want before you turn blocking on.
What to do with what it finds
Monitoring only helps if someone looks at the results. For each group of findings, decide:
- It’s an attack. Good: that’s what blocking will stop.
- It’s expected traffic. Your app really does send this. Add a narrow exception for that rule, on that field, on that route, rather than switching the rule off everywhere.
In DBshieldX this is the review queue: findings are grouped, you mark each group as an attack or expected, and an “expected” decision becomes a precise exclusion for that rule, field and route.
When to switch to blocking
Not all at once, and not on a fixed date. Block one route at a time, once that route has shown you enough normal traffic and its findings are all explained.
DBshieldX lets a route block once it has run 7 days in monitor mode with its review queue settled. When it does block, you get an alert on the first block, and any block you later mark as expected counts as a false positive, so you can see whether blocking is safe to keep on.
Some routes may never need to block. A payment provider’s webhook, for example, can stay pinned to monitor mode while the rest of the site blocks.
Make it easy to undo
The last piece is rollback. If a block turns out to be wrong, you want to undo it in seconds, not wait for a deploy. In DBshieldX every policy change is a version, and activating an earlier version reaches every proxy in under 7 seconds with no restart.
Monitor first, review, block one route at a time, keep rollback one click away. That’s how you get the protection without the 2 a.m. phone call.
Read more about how the DBshieldX rollout works, or book a demo to try monitor mode on your own site.