Proxy *.example.com to *.localTLD?

Question

Nginx

It is necessary to proxy http requests *.example.com to *.localTLD, and if somedomain.localTLD does not resolve, you need to throw it on the default page (I think this can be done through the error page for 502 Bad gateway).
How to make such a tricky proxy with undefined domains in nginx, lighttpd, apache?

Answer 1

Then you can write in

server_name default;
if ($host ~* (.*).example.com) {
    set $host_prefix $1;
    rewrite ^.*$ http://$host_prefix.localTLD/ permanent;
}

Answer 2

For Nginx something like this

server {
    listen 0.0.0.0:80;
    server_name www.example.com

    location / {
        # Proxy
        proxy_pass http://somedomain.localTLD;
        # Catch errors for processing before issuing to the client
        proxy_intercept_errors on;

        # additional options if needed
        # for example, if you are proxying to IP, you usually need to specify the host
        # proxy_set_header Host 'somedomain.localTLD';
        # Or
        # proxy_read_timeout 60;
    }
    location /pages/ {
        root /var/www/;
    }

    # Further error handling
    error_page 502 503 504 /50x.html;
    # Or if you need to answer 200 and give another page then
    # error_page 502 503 504 =200 /pages/page.html;
}

By proxying
wiki.nginx.org/HttpProxyModule
By errors
wiki.nginx.org/HttpCoreModule#error_page