Did a google search right after the email and realized my mistake. They
are equivalent.
RFC 2616, section 4.2:
Multiple message-header fields with the same field-name MAY be
present in a message if and only if the entire field-value for that
header field is defined as a comma-separated list [i.e., #(values)].
It MUST be possible to combine the multiple header fields into one
"field-name: field-value" pair, without changing the semantics of the
message, by appending each subsequent field-value to the first, each
separated by a comma. The order in which header fields with the same
field-name are received is therefore significant to the interpretation
of the combined field value, and thus a proxy MUST NOT change the
order of these field values when a message is forwarded.
Xing
Poul-Henning Kamp wrote:
> In message <451819FA.1060802 at litespeedtech.com>, "xing at litespeedtech.com" write
> s:
>> Source: http://varnish.projects.linpro.no/changeset/1121
>>
>> It appears it's missing a condition where varnish need to rewrite/append
>> to the x-forwarded-for header if it already exists in the incoming http
>> request instead of outputting a new/duplicate header.
>
> According to RFC2616 multiple headers append, they don't replace
> each other.
>
> So:
> X-Forewarded-for: 10.0.0.2, 10.0.0.3
> and
> X-Forewarded-for: 10.0.0.2
> X-Forewarded-for: 10.0.0.3
>
> should have the same semantic meaning.
>