HTTP: How should I respond to "Range: bytes=" when Range is unsupported?

Question

What is the correct response to a GET request with the header field Range: bytes=278528- if Range is not supported?

Reading the HTTP header definitions (http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html) i think i should at least set: Accept-Ranges: none, but it clearly states that

Clients MAY generate byte-range requests without having received this header for the resource involved.

So, if a client requests a range, should I:

• Reply with the whole file from byte 0?
• Reply with some status error? (400/406/416/501) see: http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html

Answer 1

You may ignore it, as the spec says. To be precise:

• If you support it, you return a status code of 206 Partial Content and include the proper headers like Content-Range.
• If you don’t support it, you return a 200 OK as normal.

I have not tested this, but the spec seems pretty clear. I have seen this work — using wget or curl to resume an interrupted download will properly restart from the beginning if the server does not support the Range header.

Answer 2

RFC2616 section 14.35.2 says:

A server MAY ignore the Range header.