There are several FEATURE() macros which allow you to make use of the maps supported by sendmail:
| Feature | Explanation |
|---|---|
| FEATURE(virtusertable) | This map allows you to support virtual domains on a single
mail server. Here's an example database:
info@foo.com foo-info info@bar.com bar-info joe@bar.com error:nouser No such user here jax@bar.com error:D.S.N:unavailable Address invalid @baz.org jane@example.net @foo.org %1@example.com old+*@foo.org new+%2@example.comEmail sent to the addresses on the left will be delivered to the corresponding address on the right. If the address on the right starts with error:, the mail is bounced with the specified error message. If the address on the left does not have a user name, all users at the specified domain will be sent to the address on the right, and the %1 token will be replaced with the username from the original address. If the original address is of the form "user+detail", it will match an entry of user+* on the left, and the token %2 will be replaced with the original "detail" string. The default filename for this database is /etc/mail/virtusertable. |
| FEATURE(domaintable) | Allows for selective rewriting of domain names. For
example, the entry ux4.cso.uiuc.edu students.uiuc.edu would
cause all email for ux4.cso.uiuc.edu to be processed as
students.uiuc.edu. The default filename for this database is /etc/mail/domaintable. |
| FEATURE(mailertable) | A mailertable is a database which maps certain hosts or
domains to a mailer:host pair. It is used for redirecting mail
addressed to a certain host or domain to a specific destination host
using a specific mailer (for example, for using phquery). The default filename for this database is /etc/mail/mailertable. |
| FEATURE(access_db) | This sets up an access control database, which allows the
administrator to control what users and hosts are allowed to send mail
to the local machine or are allowed to relay mail through the local
machine. See the Anti-Spam page for more
information. The default filename for this database is /etc/mail/access. |
Each feature macro accepts an optional argument which can override the default map type and database name. For example, the default filename for the mailertable map is /etc/mail/mailertable. To force it to use a dbm map using the file /etc/mailmap, you would use something like this:
FEATURE(mailertable, dbm -o /etc/mailmap)Note that using -o before the filename tells sendmail that the map is optional, so that it is not considered an error if the map does not exist.
