How do I deny a user accessing particular website? For example deny access to a website called foo.com.
Squid cache is a popular open source web proxy server and web cache software.
It has a wide variety of uses, from speeding up a web server by caching repeated requests, to caching web, DNS and other network lookups for a group of people sharing network resources, to aiding security by filtering traffic.
Squid has powerful ACL (access control list). The primary use of the acl system is to implement simple access control.
How to deny a user from accessing particular site?
To block site called foo.com you need to add following two lines to your squid configuration file.
# vi /etc/squid/squid.conf
Search for `Access Controls' and append following two lines:
acl blocksites dstdomain .foo.com
http_access deny blocksites
Save and close the file. Restart Squid:
# /etc/init.d/squid restart
Let us say you would like to deny access for anyone who browses to a URL with the word "bar" in it. Append following ACL:
acl blockregexurl url_regex -i bar
http_access deny blockregexurl
Save and close the file.