If you are using Apache, you can turn off its signature as detailed on this page: http://www.shanison.com/2012/07/05/unset-apache-response-header-protect-your-server-information/
Sites can tell what server software you are running through the Server
and X-Powered-By
headers, as well as by message placed on error pages by the server. Use the following directives in httpd.conf
to turn them off:
ServerSignature Off
ServerTokens Prod
Header unset Server
Header unset X-Powered-By
For the Header
command to be used, you'll need to be running Apache 2.x or higher with mod_headers enabled:
LoadModule headers_module modules/mod_headers.so