I have a domain name that is using a public IP, when I send two requests, one to the domain name and one to the IP I get different headers in each one, in one of them 4 cookies are set, in the other one only 2 are set. Using nslookup and some online tools, I can see the domain name is linked with the ip, so I'm finally testing the same thing (IP and domain name) but getting different responses. The public IP is translated into one private inside my LAN, the firewall that is making this does not insert anything. This is really weird.
What can be wrong?