I have successfully installed Squid 3 on Centos 5.7; and after I follow the guide:- https://dvas0004.wordpress.com/2011/03/22/squid-transparent-ssl-interception/. Now I have the following two lines in my squid.conf:- http_port <Internal_IP>:8080 transparent https_port <Internal_IP>:3128 ssl-bump transparent cert=/etc/pki/CA/server.crt key=/etc/pki/CA/private/server.key Now users start receiving a warning for each time they access any HTTPS site about certificates mismatch including the sites included in "ssl_bump deny *"