I have a strange issue whereby including the following syntax in my Apache 2.4.1 httpd.conf causes "502 Bad Gateway" errors when retrieving swf files via HAproxy:
AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css application/x-javascript text/javascript
When I remove this config line the 502 Bad Gateway error goes away.
The server returns these response headers on a successful request:
Date: Wed, 11 Apr 2012 20:24:12 GMT
Server: Apache
Connection: close
Transfer-Encoding: chunked
Content-Type: text/html; charset=utf-8
200 OK
I fixed this by updating to Apache 2.4.2 (there was a mod_deflate seg fault bug in 2.4.1) and adding:
Header append Vary User-Agent
Beneath the AddOutputFilterByType line.