visible_hostname

Use this directive when Squid can't determine the fully qualified domain name on its own or if you want to present a special, external name to the world. Squid uses this name in error messages, FTP directory listings, X-Cache header values, cache announcements, and for internal URLs.

Squid also puts the visible hostname into HTTP Via headers, unless you also define the unique_hostname directive. Note that you must use unique_hostname if you have a cluster of caches that have the same visible hostname.

visible_hostname hostname

visible_hostname my.host.name