The 504 Gateway Timeout error occurs when an intermediary server (proxy, CDN) didn't receive a response from the backend within the allocated time. The backend is probably too slow or blocked.
These errors often indicate performance issues requiring optimization.
Symptoms
- HTTP 504 code: explicit Gateway Timeout.
- Slow requests before failure: the request takes long before returning 504.
- Only certain endpoints: often limited to heavy endpoints (reports, exports).
Common Causes
- Slow DB query: unoptimized query taking too long.
- Slow third-party API: synchronous call to an external service that doesn't respond.
- Heavy processing: intensive computation or large file generation.
- Timeout too short: proxy configuration with insufficient timeout.
Automate with MoniTao
- 504 alerts: specifically monitor timeouts.
- Latency monitoring: alert on degradation before the timeout.
Frequently Asked Questions
Should I increase the timeout?
Only if necessary. Prefer optimizing the backend rather than masking the problem.
How to identify the slow query?
Enable slow query logs, use an APM, or add application logging.
What's the difference between 504 and 408?
504 = timeout from proxy to backend. 408 = timeout from client to server.
Can MoniTao measure time before 504?
Yes, response time is recorded even for failed requests.
Ready to Sleep Soundly?
Start free, no credit card required.