server {
        listen 80;
        server_name sub.example.com;

        access_log /var/www/postfixadmin/log/access.log main;
        error_log /var/www/postfixadmin/log/error.log;

        location ^~ /admin {
                alias /var/www/postfixadmin/postfixadmin;
                index index.php;


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