HTTP 401 Unauthorized vs 504 Gateway Timeout
HTTP 401 (Unauthorized) is a 4xx Client Error response, while 504 (Gateway Timeout) is a 5xx Server Error response. 401 indicates that the request requires user authentication. The response includes a WWW-Authenticate header indicating the authentication scheme. In contrast, 504 means that the server, acting as a gateway or proxy, did not receive a timely response from the upstream server.
Description
The request requires user authentication. The response includes a WWW-Authenticate header indicating the authentication scheme.
When You See It
When accessing a protected resource without credentials or with expired tokens.
How to Fix
Include valid authentication credentials (API key, Bearer token, Basic auth) in the Authorization header.
Description
The server, acting as a gateway or proxy, did not receive a timely response from the upstream server.
When You See It
When an upstream server is too slow to respond within the proxy's timeout window.
How to Fix
Increase proxy timeout settings. Optimize upstream server performance. Check for long-running queries.
Key Differences
401 is a 4xx Client Error response, while 504 is a 5xx Server Error response.
HTTP 401: The request requires user authentication. The response includes a WWW-Authenticate header indicating the authentication scheme.
HTTP 504: The server, acting as a gateway or proxy, did not receive a timely response from the upstream server.
You encounter 401 when when accessing a protected resource without credentials or with expired tokens.
You encounter 504 when when an upstream server is too slow to respond within the proxy's timeout window.
When to Use Which
For 401 (Unauthorized): Include valid authentication credentials (API key, Bearer token, Basic auth) in the Authorization header. For 504 (Gateway Timeout): Increase proxy timeout settings. Optimize upstream server performance. Check for long-running queries.