Apache web server allows server access based upon various conditions. For example you just want to restrict access to url http://subdomain.domain.com/ (mapped to /var/www/subdomain directory) from 192.168.1.0/24 network (within intranet).

Apache provides access control based on client hostname, IP address, or other characteristics of the client request using mod_access module.

Read here while i still didnt finish this post.

https://www.cyberciti.biz/faq/apache-restrict-access-based-on-ip-address-to-selected-directories/

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