I've made a website with Ruby and FastCGI, and it works great under Apache. I'd like to switch to nginx, but I can't get it working.
The website is made of two processes: one takes care of AJAX calls, the other takes care of the rest.
So far I figured out I should use spawn-fcgi to start my workers and bind them to a socket. Because I'd like to have multiple workers, I also use multiwatch.
The problem is, whenever I try to access to a page, I get a 502 error, and the following line in error.log:
2013/04/03 23:58:39 [error] 1450#0: *1 upstream prematurely closed connection while reading response header from upstream, client: 127.0.0.1, server: v2.localhost, request: "GET / HTTP/1.1", upstream: "http://unix:/run/fastcgi/site-v2.main.sock:/", host: "v2.localhost:8000"
So no worker ever answer the request.
netstat -x doesn't display the socket at all, but it seems like it's in use, because if I try to launch my start script twice it says
spawn-fcgi: socket is already in use, can't spawn.
One last thing: if I launch my start script and doesn't try to request a page, the multiwatch processes and the workers terminate properly with one
kill to multiwatch. But if I request a page, the multiwatch supposed to send the response and all its children workers sort of hang. I have to
kill -9 them all.
The site's entry points look like this:
require 'fcgi' FCGI.each do |req| process req end
My startup script:
USER=www-site-v2 GROUP=www-site-v2 SOCK_MODE=0660 NB_WORKERS_MAIN=4 NB_WORKERS_AJAX=4 MULTIWATCH_BIN=/usr/bin/multiwatch APP_MAIN=/var/www/site-v2/www/main.rb APP_AJAX=/var/www/site-v2/www/ajax.rb PID_MAIN=/run/fastcgi/site-v2.main.pid PID_AJAX=/run/fastcgi/site-v2.ajax.pid SOCK_MAIN=/run/fastcgi/site-v2.main.sock SOCK_AJAX=/run/fastcgi/site-v2.ajax.sock SPAWN_BIN=/usr/bin/spawn-fcgi SPAWN_ARGS="-u $USER -g $GROUP -M $SOCK_MODE -d /var/www/site-v2/www" SPAWN_ARGS_MAIN="-s $SOCK_MAIN -P $PID_MAIN" SPAWN_ARGS_AJAX="-s $SOCK_AJAX -P $PID_AJAX" case "$1" in start) test \! -d /run/fastcgi && mkdir /run/fastcgi $SPAWN_BIN $SPAWN_ARGS $SPAWN_ARGS_MAIN -- $MULTIWATCH_BIN -f $NB_WORKERS_MAIN -- $APP_MAIN && \ $SPAWN_BIN $SPAWN_ARGS $SPAWN_ARGS_AJAX -- $MULTIWATCH_BIN -f $NB_WORKERS_AJAX -- $APP_AJAX ;; stop) test -f $PID_MAIN && kill `cat $PID_MAIN` test -f $PID_AJAX && kill `cat $PID_AJAX` esac
My nginx configuration file: