Apache by default announces all sorts of information about itself when you make a connection to it :-
$ lynx -head http://some-server-fqdn/ HTTP/1.1 302 Found Date: Thu, 31 May 2018 12:18:22 GMT Server: Apache/2.2.15 (CentOS) Location: https://t-oala-idp-01.iso.port.ac.uk/ Connection: close Content-Type: text/html; charset=iso-8859-1
This can be fixed by simply changing the ServerTokens Apache configuration option to “minimal”. This is found in either security.conf or in global.conf somewhere under /etc/apache2 (or elsewhere if Apache has been set up in a strange way).
Make the change and restart Apache in the usual way – apachectl configtest and then apachectl graceful.