Why does nginx respond to IP address without a default_server directive?

koenig

11/28/23, 8:58 AM

I have an nginx webserver with two sites that listen to port 80 for two domains: dom.net and dom.se

In sites-enabled I have files for each of these, dom.net.site and dom.se.site, which are identical but for the server_name directive. It is either server_name dom.net *.dom.net; or server_name dom.se *.dom.se;. The rest is virtually the same but for a location to help me debug and it looks like this (for the .net site):

  location /check {
    return 200 'dom.net';
    add_header Content-Type text/plain;
  }

What I don't understand is why when I go to http://my-server-ip/check I get the same response as if I go to http://server.dom.net/check. I have no default_server directive in any of the site files and still nginx responds to the ip-address.

And why did it pick http://server.dom.net and not http://server.dom.se?

Very confused.

245

1 + 4

nginx

Gerald Schneider

11/28/23, 9:01 AM

usually alphabetical order.

Drifter104

11/28/23, 9:24 AM

Type nginx -T and you'll see the complete nginx.conf the one that is higher up in the config file will be the site that handles all other requests

Richard Smith

11/28/23, 10:42 AM

See [how Nginx processes a request](http://nginx.org/en/docs/http/request_processing.html).

Tero Kilkanen

11/28/23, 3:49 PM

This is a design choice nginx developers have made at some point: There is no explicit "null" `server` block for default. Some `server` block is always used as the default one. Which one it is, can be seen from Richard's link above. Also, nginx listens on port 80 / 443 or anything else that is configured. It must answer something to every request. So, you cannot prevent answering to an IP address without specifying a `server` block for that.

Score:0

Server

Salar

11/28/23, 12:53 PM

There is a default config for nginx in the following path : /etc/nginx/nginx.conf if you read it there is a block with "http{}" syntax and in that block there is a line that says

include /etc/nginx/sites-enabled/*

So what nginx will do is loading files in that directory in order ( alphabetical order ) as "Gerald Schneider" mentioned in comment

+ 0

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