HTTP 425 Too Early vs 506 Variant Also Negotiates
HTTP 425 (Too Early) is a 4xx Client Error response, while 506 (Variant Also Negotiates) is a 5xx Server Error response. 425 indicates that the server is unwilling to risk processing a request that might be replayed. Used with TLS 1.3 early data (0-RTT). In contrast, 506 means that the server has an internal configuration error: the chosen variant resource is configured to engage in content negotiation itself.
Description
The server is unwilling to risk processing a request that might be replayed. Used with TLS 1.3 early data (0-RTT).
When You See It
When a server rejects a request sent as TLS 1.3 early data due to replay risk.
How to Fix
Retry the request after the TLS handshake completes.
Description
The server has an internal configuration error: the chosen variant resource is configured to engage in content negotiation itself.
When You See It
Rare. Indicates a misconfigured server-side content negotiation loop.
How to Fix
Fix the server's content negotiation configuration.
Key Differences
425 is a 4xx Client Error response, while 506 is a 5xx Server Error response.
HTTP 425: The server is unwilling to risk processing a request that might be replayed. Used with TLS 1.3 early data (0-RTT).
HTTP 506: The server has an internal configuration error: the chosen variant resource is configured to engage in content negotiation itself.
You encounter 425 when when a server rejects a request sent as TLS 1.3 early data due to replay risk.
You encounter 506 when rare. Indicates a misconfigured server-side content negotiation loop.
When to Use Which
For 425 (Too Early): Retry the request after the TLS handshake completes. For 506 (Variant Also Negotiates): Fix the server's content negotiation configuration.