lightmy.dayINSTANT ANSWERS

Server error

HTTP 502: Bad Gateway

HTTP 502 means a gateway received a bad response from an upstream server.

Meaning

A proxy, gateway, or load balancer could not use the response from another server.

Common causes

Upstream crashes, invalid responses, DNS issues, or proxy misconfiguration can cause it.

What to check

Check upstream health, gateway logs, DNS, TLS, and proxy timeout or routing settings.

Example response

HTTP/1.1 502 Bad Gateway

References

Registry: IANA HTTP Status Code Registry
Spec: RFC 9110 §15.6.3
Guide: MDN 502 Bad Gateway

Related HTTP status codes

Nearby codes often answer the next debugging question.

500 Internal Server ErrorHTTP 500 means the server hit an internal error.503 Service UnavailableHTTP 503 means the service is temporarily unavailable.504 Gateway TimeoutHTTP 504 means a gateway timed out waiting for an upstream server.