Sendmail use “access” database to control who can use this email server to send email out.
It’s easy, just edit this file
/etc/mail/access
, but access is a database file, after you edit it you need to recreate database map
makemap hash /etc/mail/access < /etc/mail/access
Put your control list in the at the end of the file:
[email protected] REJECT cyberspammer.com REJECT TLD REJECT 192.168.0 RELAY 192.168.1 OK
REJECT: reject all email from that source RELAY: allow that IP range to use our server as a relay. OK: allow to send any email even though it's blocked in some other rules.