504 Gateway Timeout
A proxy waited for the backend and gave up. The request may STILL have executed.
504Server error
- What it means
- A proxy waited for the backend and gave up. The request may STILL have executed.
- In practice
- The proxy’s patience ran out before the application answered — a slow query, a stuck external call, work that genuinely takes longer than the proxy allows. The dangerous subtlety: the backend may still be running the request and may yet finish it. Never retry a non-idempotent request after a 504 without checking whether it happened; that is how double charges are born. Long jobs belong in a queue with a status endpoint, not behind a proxy timeout.
- Whose problem is it?
- The server (or something behind it). The request may have been fine.
Often confused with