sendmail, 4th Edition

FEATURE(virtuser_entire_domain)

Match subdomains in the virtual user table V8.10 and later

Ordinarily, domains listed in the $=w class or the $={VirtHost} class are looked up in the virtual user table as is, meaning that only host-for-host or domain-for-domain matches are made. This FEATURE(virtuser_entire_domain) changes that behavior and allows subdomains to also be looked up.

Consider, for example, that the domain wanted.com is listed with the VIRTUSER_DOMAIN mc configuration macro (VIRTUSER_DOMAIN mc macro on page 647) and the following lines are listed in the virtual host table:

[e-mail]         [e-mail]
[e-mail]   [e-mail]

Here, mail sent to [e-mail] would ordinarily not be looked up. But by declaring this FEATURE(virtuser_entire_domain), all hosts in the subdomain wanted.com would will be looked up, so the address [e-mail] would now find a match.