Francesc Pe?alvez:
> Lately we are receiving spam mails that apparently the mail from the and
> the to is the same. How is it possible to avoid this?. I have configured
> postfix to avoid the relay of emails and to be able to send mail through
> my postfix is necessary the auth , these emails are sent externally from
> several ips and seeing the logs of those emails are not authenticated
Postfix 3.0 and later:
/etc/postfix/main.cf:
smtpd_sender_restrictions =
permit_mynetworks
permit_sasl_authenticated
check_sender_access inline:{
{ example.com = REJECT local sender from unauthorized client }
{ other.example = REJECT local sender from unauthorized client }
}
Instead of example.com and other.example, specify your email domains.
Note: this breaks email from remote mail forwarders or from remote
distribution lists that don't reset the sender address.
Wietse
