Tag Name always_direct
Usage always_direct allow|deny [!]aclname …

Description
Here you can use ACL elements to specify requests, which should ALWAYS be forwarded directly to origin servers. This is mostly used while using cache_peer. See also never_direct . For Further reference on always_direct, please click here.

Default always_direct is by default deny.

Example
For example, to always directly forward requests for local servers use something like:
acl local-servers dstdomain .my.domain.net
always_direct allow local-servers

To always forward FTP requests directly, use
acl FTP proto FTP
always_direct allow FTP

Example for denying specific domain
acl local-external dstdomain .external.foo.net
acl local-servers dstdomain .foo.net
always_direct deny local-external
always_direct allow local-servers

Caution
There is a similar, but opposite option named ‘ never_direct’. You need to be aware that “always_direct deny foo” is NOT the same thing as “never_direct allow foo”. You may need to use a deny rule to exclude a more-specific case of some other rule.