Time for action – avoiding caching of local content

First of all, we'll need to identify the requests in which content on your local area network is being requested. So, let's say in our network, some clients have hosted FTP and HTTP servers on their machines to share content on the intranet. The client machines have IP addresses in the subnets 192.0.2.0/24 and 198.51.100.0/24. So, we need to construct an ACL list that can identify all the requests directed to these machines. The following ACL list does exactly that:

acl client_servers dst 192.0.2.0/24 198.51.100.0/24

Also, we have mail.internal.example.com and docs.internal.example.com hosted in the local network. So, let's construct an ACL list to identify all the requests to these websites:

acl internal_websites dstdomain .internal.example.com

So, as we have identified the requests for local content, we just need to instruct Squid not to cache replies to any of these requests. Therefore, we will use the access list rule cache to deny caching...