Why is nginx responding to any domain name?

I have nginx up and running with a Ruby/Sinatra app and all is well. However, I'm now trying to have a second application running from the same server and I noticed something weird. First, here's my nginx.conf: pid /tmp/nginx.pid; error_log /tmp/nginx.error.log; events { worker_connections 1024; accept_mutex off; } http { default_type application/octet-stream; access_log /tmp/nginx.access.log combined; sendfile on; tcp_nopush on; tcp_nodelay off; gzip on; gzip_http_version 1.0; gzip_proxied any; gzip_min_length 500; gzip_disable "MSIE [1-6]\."; gzip_types text/plain text/xml text/css text/comma-separated-values text/javascript application/x-javascript application/atom+xml; upstream app { server unix:/var/www/app/tmp/sockets/unicorn.sock fail_timeout=0; } server { listen 80; client_max_body_size 4G; server_name FAKE.COM; keepalive_timeout 5; root /var/www/app/public; location / { proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_set_header Host $http_host; proxy_redirect off; if (!-f $request_filename) { proxy_pass http://app; break; } } error_page 500 502 503 504 /500.html; location = /500.html { root /var/www/app/public; } } } 68,0-1 B Notice how `server_name` is set to `FAKE.COM` yet the server is responding to all hosts that hit that server via other domain names. How can I make that particular server respond only to requests for `FAKE.COM`?