How to stop Nginx redirecting to default server?

Question

I'm setting up Nginx with PHP 5.3 for multiple websites running wordpress for example. I just added a new site and it's being redirected to the default welcome page. I can't see any 'real' errors in the logs.

Here's my abbreviated nginx.conf :

http {
    access_log /var/log/nginx_access.log;
    index index.php index.html;

    server {
        listen          80 default_server;
        server_name     _;
        root            /opt/nginx/html;

        location / {
        }
    }

    server {
        listen          80;
        server_name     example.com *.example.com;                      
        rewrite ^       $scheme://www.example.com$request_uri? permanent;
    }

    server {
        listen       80;
        server_name  www.example.com;
        root /home/example/example.com;

        location / {
        }

        location ~ \.php$ {
            try_files $uri =404;
            fastcgi_pass   unix:/var/run/php5-fpm/example.sock;
            fastcgi_index  index.php;
            include        fastcgi_params;
        }

}

Answer 1

As pointed by comments, the listen directive in the server block define it as the default (source: http://nginx.org/en/docs/http/request_processing.html):

listen       80  default_server;

The following declaration is meant as an invalid server name (source: http://nginx.org/en/docs/http/server_names.html) (so it never intersect any of your valid domain) :

Server_name _; 

To fix you problem, make sure you have a server block with listen (port) and server_name (virtual host) - this one will be triggered first as you go from 'more precise to less precise' when you do virtual host names matching in nginx:

Listen 80;
Server_name your-domain-name.com;