Can Squid listen on more than one HTTP port?
Note: The information here is current for version 2.3. Yes, you can specify multiple http_port lines in your squid.conf file. Squid attempts to bind() to each port that you specify. Sometimes Squid may not be able to bind to a port, either because of permissions or because the port is already in use. If Squid can bind to at least one port, then it will continue running. If it can not bind to any of the ports, then Squid stops. With version 2.3 and later you can specify IP addresses and port numbers together (see the squid.conf comments).