By default, Postfix will forward mail from strangers (clients outside
authorized networks) to authorized remote destinations only.
Authorized remote
destinations are defined with the
relay_domains configuration
parameter. The default is to authorize all domains (and subdomains)
of the domains listed with the
mydestination parameter.
Examples (specify only one of the following):
/etc/postfix/main.cf:
relay_domains = $
mydestination (default)
relay_domains = (safe: never forward mail from strangers)
relay_domains = $
mydomain (forward mail to my domain and subdomains)
