I was beating my head against a wall for a day about a caching issue, but I think I figured the problem out now. It seems like mod_deflate is adding the 'Vary' header to all responses regardless of whether they were actually compressed or not. Here's a snippet of the HTTP session for a static HTML file:
$ curl --header 'Host: www.domain.com' -v -s -o/dev/null http://X.X.X.X/static.htm * About to connect() to X.X.X.X port 80 (#0) * Trying X.X.X.X... connected * Connected to X.X.X.X (X.X.X.X) port 80 (#0) > GET /static.htm HTTP/1.1 > User-Agent: curl/7.21.7 (x86_64-pc-linux-gnu) libcurl/7.21.7 NSS/3.12.10.0 > zlib/1.2.5 > Accept: */* > Host: www.domain.com > < HTTP/1.1 200 OK < Date: Tue, 30 Aug 2011 18:39:47 GMT < Server: Apache < Last-Modified: Tue, 30 Aug 2011 17:59:49 GMT < Accept-Ranges: bytes < Content-Length: 247 < Vary: Accept-Encoding < Cache-Control: max-age=2592000 < Connection: close < Content-Type: text/html < { [data not shown] * Closing connection #0 I then referenced the mod_deflate.c source code, and found the following: /* Even if we don't accept this request based on it not having * the Accept-Encoding, we need to note that we were looking * for this header and downstream proxies should be aware of that. */ apr_table_mergen(r->headers_out, "Vary", "Accept-Encoding"); What is the reasoning for adding the 'Vary' header even if mod_deflate does nothing with the response? Thanks, Mike --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscr...@httpd.apache.org " from the digest: users-digest-unsubscr...@httpd.apache.org For additional commands, e-mail: users-h...@httpd.apache.org
