mod_proxy+mod_cache - no upstream & set error_page?

[Scott Smith]

Hi,

I'm using Nginx with mod_proxy+mod_cache to proxy and cache specific pages.

When the upstream ($host) is down, and the page is not cached, Nginx 
returns a generic 502 page. Is it possible to use error_page?

I've tried putting error_page 502 directive in multiple places to no avail.

Here is my full config:

user daemon;
worker_processes 5;
worker_rlimit_nofile 20480;

error_log /var/log/nginx/error.log;
pid /var/run/nginx.pid;

events {
     worker_connections 4096;
     # multi_accept on;
     use epoll;
}

http {
     include /etc/nginx/mime.types;

     access_log /var/log/nginx/access.log;

     sendfile on;
     #tcp_nopush on;

     #keepalive_timeout 0;
     keepalive_timeout 65;
     tcp_nodelay on;

     gzip on;
     gzip_disable msie6;
     gzip_proxied any;

     proxy_cache_path /path/to/cache levels=1:1:2 
keys_zone=maint_cache:512m inactive=15d max_size=30g;
     proxy_hide_header Expires;
     proxy_hide_header Cache-Control;

     server {
         listen 80;
         server_name foo.bar.com;

         location /nginx_status {
             stub_status on;
             access_log off;
             allow 10.0.0.0/8;
             deny all;
         }

         root /path/to/htdocs;

         log_format cache_log '$time_local '
             '$upstream_cache_status '
             'Cache-Control: $upstream_http_cache_control '
             'Expires: $upstream_http_expires '
             '"$request" ($status) '
             '"$http_user_agent" ';

         access_log /var/log/nginx/proxy.access.log;
         access_log /var/log/nginx/proxy.cache.log cache_log;

         proxy_cache mycache;
         proxy_set_header Host $http_host;
         proxy_cache_use_stale error timeout updating http_500 http_502
             http_503 http_504 http_404;

         error_page 404 /default/index.html;

         if ($host ~* ^([a-z0-9\-]+\.([a-z]+))$) {
             set $host_with_www www.$1;
         }

         if ($host !~* ^([a-z0-9\-]+\.([a-z]+))$) {
             set $host_with_www $host;
         }

         location ~ /purge(/.*) {
             proxy_cache_purge mycache "$host_with_www$1";
             allow 10.0.0.0/8;
             deny all;
         }

         # The initial request MUST respond with HTTP 503.
         location ~ ^/$ {
             error_page 503 /503index;
             return 503;
         }

         location /503index {
             proxy_pass http://$host_with_www/path/to/index.php;
             proxy_cache_key "$host_with_www/index.php";
         }

         # If the CSS request isn't HTTP 200 some browsers don't render
         location /path/to/styles.css {
             proxy_pass http://$host_with_www/path/to/styles.css;
             proxy_cache_key "$host_with_www/styles.css";
         }

         location ~ /.*$ {
             error_page 503 /503index;
             return 503;
         }
}