HTTP

HTTP 308 Permanent Redirect vs 417 Expectation Failed

HTTP 308 (Permanent Redirect) is a 3xx Redirection response, while 417 (Expectation Failed) is a 4xx Client Error response. 308 indicates that the resource has been permanently moved. Like 301, but guarantees the HTTP method will NOT be changed. In contrast, 417 means that the server cannot meet the requirements of the Expect header.

Description

The resource has been permanently moved. Like 301, but guarantees the HTTP method will NOT be changed.

When You See It

For permanent URL changes where POST requests must remain POST.

How to Fix

Update all references to the new URL. The HTTP method is preserved.

Description

The server cannot meet the requirements of the Expect header.

When You See It

When the server doesn't support Expect: 100-continue.

How to Fix

Remove the Expect header from your request.

Key Differences

1.

308 is a 3xx Redirection response, while 417 is a 4xx Client Error response.

2.

HTTP 308: The resource has been permanently moved. Like 301, but guarantees the HTTP method will NOT be changed.

3.

HTTP 417: The server cannot meet the requirements of the Expect header.

4.

You encounter 308 when for permanent URL changes where POST requests must remain POST.

5.

You encounter 417 when when the server doesn't support Expect: 100-continue.

When to Use Which

For 308 (Permanent Redirect): Update all references to the new URL. The HTTP method is preserved. For 417 (Expectation Failed): Remove the Expect header from your request.

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