I have configured a Sendmail mail server on Red Hat Linux 9.0 for our own usage. In order to discourage improper mail usage (to keep a tab on the staffs using the mail service for sending out personal mails) as well as
for keeping a copy of all mailing transactions on a backup system, we
want to configure the mail server so that the POSTMASTER gets a copy of
all incoming and outbound mails.
Is there any way so that all incoming mails that are downloaded from my ISP's server are forwarded to the POSTMASTER email address, as well as the user for which it is intended to. For example, if someone from email@example.com sends a mail to a user on my domain (firstname.lastname@example.org), the user gets the mail, and a copy of the same email is automatically forwarded to email@example.com.
Similarly, can we configure Sendmail so that if any user on my domain sends an outbound mail, a copy of the same is sent to the Postmaster.