Mine
public text v1 · immutablemain.cf:
smtpd_restriction_classes = permit_bad_helo
permit_bad_helo = reject_unauth_destination, permit
smtpd_recipient_restrictions = reject_unknown_recipient_domain,
check_client_access cdb:/etc/postfix/helo_exceptions.hosts,
reject_unknown_helo_hostname,
reject_invalid_helo_hostname,
reject_non_fqdn_helo_hostname,
reject_unauth_destination
/etc/postfix/helo_exceptions.hosts:
192.168.3.41 permit_bad_helo