I am having a couple of problems WRT using mod_proxy_fcgi inside a balancer proxied to php-fpm. There are lots of variables in this scenario, but I think I have narrowed the issues down. The setup looks like this:
httpd -> balancer -> fcgi balancer members -> php-fpm Issue 1: PHP-FPM does not handle the "proxy:balancer" prefix in SCRIPT_FILENAME. It does handle "proxy:fcgi" as a special case (see https://bugs.php.net/bug.php?id=54152 fix by jim). So, it seems we need to also add a "proxy:balancer" exception there unless a balanced mod_proxy_fcgi member should actually be using "proxy:fcgi" instead. What are people's thoughts on the prefix that should be sent by httpd in this case? To address this for now, I have modified PHP (fpm_main.c alongside jim's existing changes). Issue 2: Once I got Issue 1 addressed, everything started working except in the case of a query string. I spent considerable time tracing and trying to figure out where the issue is occurring, but I am hoping one of you who is much more familiar with the code than I will be able to say, "Oh, look right here." The problem is that the query string is getting appended to SCRIPT_FILENAME if proxied through a balancer. FPM does not like this. It does not seem to happen in the case of proxying directly to "fcgi://...", but once I change this to "balancer://...", the query string gets added to SCRIPT_FILENAME. I believe this happened with both ProxyPass* and mod_rewrite [P]. In mod_rewrite, this should get handled in splitout_queryargs(), but somehow it is getting added back (probably in proxy_balancer_canon() which adds the query string back to r->filename?). For right now, I have done a brute-force "fix" for this by adding the code below to the beginning of send_environment() in mod_proxy_fcgi.c, before the calls to ap_add_common_vars() and ap_add_cgi_vars(). I am guessing that this isn't the ultimate fix for this issue, so I am interested in others' thoughts. + /* Remove query string from r->filename (r->args is already set and passed via QUERY_STRING) */ + q = ap_strchr_c(r->filename, '?'); + if (q != NULL) { + *q = '\0'; + }
