> Dear all, > > We have a Squid (2.6) server installed as a reverse proxy and connected to > an original-server that uses the "Expire" header field to specify when the > response should be considered stale. > > If the client requests includes a "no-cache" cache-control directive can > we assume that Squid will be forced to *reload* the cached object with a > fresh response returned by the original server (assuming that the response > has a new expiration date set)? > > The HTTP header specification > (http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9.4) says > that "the server MUST NOT use a cached copy when responding to such a > request" but does not say what should happen with the current cached > object. Would it be replaced by new response? > > What would be the behavior of Squid in case of "max-age=0" request > directive (assuming again that the response has a newer expiration date > set)? Squid would request new data, I believe. Any time Squid receives new files from an authoritative source it updates its cached copy with the new content (except possibly in cases of bug #7). A few other things come in to play such as whether its allowed to store the content returned, Vary, ETag etc. Amos
