HTTP 502 — Bad Gateway
5xx Server Error
What it means
A server acting as a proxy got an invalid response from the upstream server.
What to do about it
The application behind the proxy is down, crashed, or returned garbage. Check that the app is running and listening on the port nginx or the load balancer expects.
Where it sits
502 belongs to the 5xx family: The server failed to fulfil an apparently valid request. The fix is on the server side.
HTTP/1.1 502 Bad GatewayChecking it yourself
# see the status code and headers only
curl -sI https://example.com/path
# follow redirects and print each hop
curl -sIL -o /dev/null -w "%{http_code} %{url_effective}\n" https://example.com/path
# JavaScript
const r = await fetch(url);
console.log(r.status, r.statusText);