Nginx proxy_pass, define a non-match case?

Question

I've got 2 files with proxy_pass :

server {
    listen 80;
    server_name www.domain1.fr;

    location / {
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header HOST $http_host;
        proxy_set_header X-NginX-Proxy true;

        proxy_pass http://127.0.0.1:2368;
        proxy_redirect off;
    }
}

and

server {
    listen 80;
    server_name www.domain2.fr;

    location / {
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header HOST $http_host;
        proxy_set_header X-NginX-Proxy true;

        proxy_pass http://127.0.0.1:2369;
        proxy_redirect off;
    }
}

They both work fine.

Now, if I go to this server through another domain name (defined on my DNS server targeting the same IP address), eg. www.domain3.fr, instead of a 404, I've got the same result as www.domain2.fr !

I guess it's because of the last location /, but how can I do a 404 error if the domain name is not the same than server_name ?

Answer 1

I've answered this question so many times I'm thinking of finding a way to make it generic so I could share it when there's a question is asked.

Here's the other answers if you would like to look at it

• Nginx Subdomain accessible on subdomain its not configured for
• nginx subdomain ssl redirect redirects top level domain
• nginx reverse proxy redirecting to wrong domain

you can read on any one why this is happening, on this reference link How nginx processes a request

Simple answer is a small server block to prevent it

server {
  listen 80 default_server;
  # return a code maybe or do any thing
  return 404;
}

of course reload nginx after that to reflect the settings.

Answer 2

Well, I had to add a new config :

server {
    listen 80 default_server;
    server_name _;
    access_log off;
    return 404;
}

To be a "catch all".
Source : NGINX multiple server blocks with reverse proxy