NginX & Plesk: 502

Question

Having server with CentOS and Plesk. Installed nginx right how it's discribed here: http://gudym.net/plesk-nginx.html But now if i go to mysupermegasite.com I'm getting

502 Bad Gateway
nginx/0.8.55

This error seems to be because Apache doesn't respond to NginX. BUT if I get to mysupermegasite.com:8080 i see the correct page. So Apache seems to run fine at 8080-th port. And in that instruction Apache supposed to be at 8080-th! So this seems to be correct.

Also in

/var/www/vhosts/mysupermegasite.com/conf/nginx.conf I see:

  server {
  listen      80;
  server_name mysupermegasite.com www.mysupermegasite.com ;
  error_log /var/www/vhosts/mysupermegasite.com/statistics/logs/error_log.nginx warn;

  location / {
    proxy_pass  http://www.mysupermegasite.com:8080$request_uri;
    include  /etc/nginx/proxy.conf;
  }

  location ~*/w3tc/* {
    proxy_pass  http://www.mysupermegasite.com:8080$request_uri;
    include  /etc/nginx/proxy.conf;
  }

  location ~* ^.+\.(jpg|jpeg|gif|png|css|zip|tgz|gz|rar|bz2|doc|xls|exe|pdf|ppt|txt|tar|wav|bmp|rtf|js|ico|swf)$ {
    root /var/www/vhosts/mysupermegasite.com/public_html;
    expires 7d;
  }
 }

So... as I understand this, it directs nginx to mysupermegasite.com:8080 to get the page from Apache.

Let's see the error log vi /var/www/vhosts/mysupermegasite.com/statistics/logs/error_log.nginx

2012/02/07 07:35:29 [error] 11758#0: *1 mysupermegasite.com could not be resolved (110: Operation timed out), client: 89.112.11.xx, server: mysupermegasite.com, request: "GET / HTTP/1.1", host: "mysupermegasite.com"

Okay, it can't resolve this domain. Buy why? I even added

127.0.0.1 mysupermegasite.com

to the /etc/hosts file

If I try

wget mysupermegasite.com:8080

it downloads the page. But why NginX can't resolve this host?

What's wrong? Where to look for the reason?

Answer 1

Seems that your system can't resolve this domain. nginx doesn't use /etc/hosts file to resolve domains. Check that /etc/resolv.conf contains correct nameservers. I suggest you to explicitly specify IP address or localhost:

location / {
    proxy_pass http://localhost:8080;
}

Or you can specify better resolver for nginx, that knows this domain, instead of resolvers from /etc/resolv.conf:

resolver 192.0.2.1;

You can check if resolver knows the domain:

# dig mysupermegasite.com @192.0.2.1