HTTP 200 OK vs 502 Bad Gateway
HTTP 200 (OK) is a 2xx Success response, while 502 (Bad Gateway) is a 5xx Server Error response. 200 indicates that the request succeeded. The meaning depends on the HTTP method: GET returns the resource, POST reports the action result, HEAD returns headers only. In contrast, 502 means that the server, acting as a gateway or proxy, received an invalid response from the upstream server.
Description
The request succeeded. The meaning depends on the HTTP method: GET returns the resource, POST reports the action result, HEAD returns headers only.
When You See It
The most common HTTP response — indicates the request was processed successfully.
How to Fix
No fix needed. The request succeeded as expected.
Description
The server, acting as a gateway or proxy, received an invalid response from the upstream server.
When You See It
When Nginx/Apache can't reach the application server (e.g., Gunicorn is down, upstream timeout).
How to Fix
Check if the upstream server is running. Verify proxy configuration. Check for upstream timeouts.
Key Differences
200 is a 2xx Success response, while 502 is a 5xx Server Error response.
HTTP 200: The request succeeded. The meaning depends on the HTTP method: GET returns the resource, POST reports the action result, HEAD returns headers only.
HTTP 502: The server, acting as a gateway or proxy, received an invalid response from the upstream server.
You encounter 200 when the most common HTTP response — indicates the request was processed successfully.
You encounter 502 when when Nginx/Apache can't reach the application server (e.g., Gunicorn is down, upstream timeout).
When to Use Which
For 200 (OK): No fix needed. The request succeeded as expected. For 502 (Bad Gateway): Check if the upstream server is running. Verify proxy configuration. Check for upstream timeouts.