I had someone tell me today that they were unable to send email to their customer from the mail server because they got the following error:
***************************************** Failed Recipient: u...@example.tld Reason: Remote host said: 554 Service unavailable; Client host [vss155.webhosting-email.com] blocked by zen.spamhaus.org; http://www.spamhaus.org/query/bl?ip=74.235.192.80 ***************************************** Now I noticed that they were able to send me emails fine to my Postfix mail server shown below: Oct 22 13:55:32 mail postfix/smtpd[10081]: connect from vss155.webhosting-email.com[64.38.48.101] Oct 22 13:55:32 mail postfix/smtpd[10081]: B25E1207AE: client=vss155.webhosting-email.com[64.38.48.101] Oct 22 13:55:33 mail postfix/cleanup[10084]: B25E1207AE: message-id=<003601cb7211$49b46240$dd1d26...@com> Oct 22 13:55:33 mail postfix/qmgr[1053]: B25E1207AE: from=<u...@harbormarketinggroup.com>, size=2085, nrcpt=1 (queue active) Oct 22 13:55:33 mail postfix/smtpd[10081]: disconnect from vss155.webhosting-email.com[64.38.48.101] Oct 22 13:55:35 mail postfix/pickup[9980]: 098F4207B4: uid=5001 from=<u...@harbormarketinggroup.com> Oct 22 13:55:35 mail postfix/cleanup[10084]: 098F4207B4: message-id=<003601cb7211$49b46240$dd1d26...@com> Oct 22 13:55:35 mail postfix/qmgr[1053]: B25E1207AE: removed Oct 22 13:55:35 mail postfix/qmgr[1053]: 098F4207B4: from=<u...@harbormarketinggroup.com>, size=2376, nrcpt=1 (queue active) Oct 22 13:55:35 mail postfix/local[10090]: 098F4207B4: to=<car...@iamghost.com>, relay=local, delay=0.12, delays=0.08/0/0/0.04, dsn=2.0.0, status=sent (delivered to maildir) Oct 22 13:55:35 mail postfix/qmgr[1053]: 098F4207B4: removed I am confused because if I have a zen.spamhaus RBL check in my main.cf so should this not also be blocked to communicate with mail Postfix mail server? I am posting my 'postconf -n' below: alias_database = $alias_maps alias_maps = hash:/etc/postfix/aliases bounce_queue_lifetime = 1d broken_sasl_auth_clients = yes command_directory = /usr/sbin config_directory = /etc/postfix daemon_directory = /usr/lib/postfix delay_warning_time = 4h home_mailbox = mail/ html_directory = no inet_interfaces = all inet_protocols = ipv4 mail_owner = postfix manpage_directory = /usr/share/man message_size_limit = 20480000 mydestination = $myhostname, $mydomain, mail.$mydomain mydomain = iamghost.com myhostname = mail.iamghost.com mynetworks = $config_directory/mynetworks myorigin = $mydomain newaliases_path = /usr/bin/newaliases queue_directory = /var/spool/postfix readme_directory = no recipient_delimiter = + relayhost = sample_directory = /etc/postfix/sample sendmail_path = /usr/sbin/sendmail setgid_group = postdrop smtp_helo_timeout = 60s smtp_tls_session_cache_database = btree:/var/lib/postfix/smtp_scache smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination, reject_non_fqdn_recipient, reject_unknown_recipient_domain, reject_non_fqdn_helo_hostname, reject_invalid_helo_hostname, reject_rbl_client zen.spamhaus.org, reject_rbl_client bl.spamcop.net, check_policy_service inet:127.0.0.1:10030 smtpd_sasl_auth_enable = yes smtpd_sasl_path = /var/run/dovecot/auth-client smtpd_sasl_security_options = noanonymous smtpd_sasl_type = dovecot smtpd_sender_restrictions = permit_sasl_authenticated, permit_mynetworks smtpd_tls_cert_file = /etc/ssl/certs/mail.crt smtpd_tls_key_file = /etc/ssl/private/mail.key smtpd_tls_loglevel = 1 smtpd_tls_security_level = may smtpd_tls_session_cache_database = btree:/var/lib/postfix/smtpd_scache unknown_local_recipient_reject_code = 450 Can anyone tell me if I am mis-understanding anything? Why would someone who's blacklisted on the PBL from Spamhaus be allowed to send me email when it's listed as RBL in 'smtpd_recipient_restrictions'?