I can hide Nginx version by using server_tokens option set to off. But not able to change the Nginx Server signature.
Steps I did,
1.) Change the Nginx serve
If you are working in ubuntu then
First install nginx-extras
nginx-extras
sudo apt-get install nginx-extras
Go to /etc/nginx/nginx.conf and under http add:
/etc/nginx/nginx.conf
http
http { more_set_headers "Server: Your_New_Server_Name"; server_tokens off; }
Restart nginx
sudo service nginx restart