SERVER_NAME and fastcgi

Forgive me if this has been covered before, but I didn’t see anything
while searching.

I have a server setup similar to:

server {
listen 80;
server_name domain.com someotherdomain.com somethirddomain.com;
rewrite “^(.*)$” http://www.domain.com$1 permanent;
}

server {
listen 80;
server_name www.domain.com *.domain.com;
server_name_in_redirect off;

}

I had some issues with nginx redirecting to *.domain.com when people
would omit a trailing / on physical directories in requests, the only
fix I was able to ascertain was setting it up as I have mentioned.

At any rate, if a client makes a request that bypasses our loadbalancer
directly via wwwX.domain.com, it gets caught by the second server block
as intended. The problem however is that $server_name gets set to the
first match in the server_name directive (as mentioned in the
documentation). My fastcgi_param for SERVER_NAME is set to $server_name
(the default).

The problem is that I need the ability to discern that someone is
hitting a server directly via $_SERVER[‘SERVER_NAME’], and under this
default configuration I am unable to do so since even direct requests to
webservers end up having $server_name set to www.domain.com, rather than
what the Host: was set to (wwwX.domain.com).

I understand that there is also the $host variable, but I was not sure
what the best practice is as far as reliably duplicating the SERVER_NAME
functionality of Apache.

Any help would be appreciated!

Thanks,
-Kyle

Posted at Nginx Forum:

On Wed, Sep 15, 2010 at 09:34:56PM -0400, KyleChristensen wrote:

fix I was able to ascertain was setting it up as I have mentioned.
default configuration I am unable to do so since even direct requests to
webservers end up having $server_name set to www.domain.com, rather than
what the Host: was set to (wwwX.domain.com).

I understand that there is also the $host variable, but I was not sure
what the best practice is as far as reliably duplicating the SERVER_NAME
functionality of Apache.

$server_name value is the first name in a server_name directive,
$http_host value is a value of a “Host” header line,
$host value is a value of a “Host” header line OR, if there is not
the header line, is a value of the $server_name.


Igor S.
http://sysoev.ru/en/