sendmail, 4th Edition

F=A

User can be to the LHS of an alias V8.7 and later

Prior to V8.7 sendmail, only the local delivery agent could cause addresses to be looked up in the aliases(5) database (Local Must Be Local on page 462). Beginning with V8.7 sendmail, any delivery agent that has an F=A delivery agent flag set will cause its $: address to be looked up on the lefthand side of the aliases(5) file.

For example, the F=A delivery agent flag can be used to design a local-clone delivery agent that recognizes certain nonlocal addresses as local for aliasing purposes:^[291]

R$+ <@ FIRE.WALL>     $#firelocal $: $[e-mail]

This allows an alias file such as the following to legally exist:

[e-mail]:   [e-mail]

For example, as a safety net (and if the F=5 delivery agent flag is also specified), any address that is not found in the aliases(5) database will be passed to the localaddr rule set 5 (The localaddr Rule Set 5 on page 700) where another delivery agent can be selected.

In configuration files prior to version 6 (The V Configuration Command on page 580), the F=A delivery agent flag is automatically set for the local delivery agent.

^{[291] *} This example is somewhat, contrived because the same thing can be done in a more versatile manner with FEATURE(mailertable) (FEATURE(mailertable) on page 629).