I have recently started to deploy a mail server with Postfix and Dovecot on my Ubuntu 18.04. LTS. Unfortunately recieving mails does not work, and I have yet to understand why.
In Dovecot, I have enabled IMAPS on port 993, LMTP over 127.0.0.1:24 and SMTP-auth via the
unix_listener. The authentication is against a LDAP-Server, that should also provide all users for my mail server.
user_filter in my
dovecot-ldap.conf.ext is set to
(&(objectClass=rspfMember)(uid=%Ln)), as all users with this objectClass should be able to send/recieve mails. The
uid of the LDAP entries equals the local part of the mail address, thus I used
%Ln for the filter.
I enabled the following restrictions:
smtpd_recipient_restrictions = reject_non_fqdn_sender, reject_non_fqdn_recipient, reject_unknown_sender_domain, reject_unknown_recipient_domain, permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination, reject_rbl_client zen.spamhaus.org, reject_rbl_client ix.dnsbl.manitu.net, check_policy_service inet:127.0.0.1:10023, reject_unverified_recipient, permit
First of all, running
sudo doveadm user myusername finds the user I am searching for, and
sudo doveadm auth test myusername mypassword returns
auth succeeded, so I am assuming that my LDAP setup is correct.
Sending mails from the accounts is also possible, so I can login to the account via SMTP with any mail client, and so it succeeds with IMAP.
If I send a mail to one of the users, I can see in the log files that the RBL restrictions as well as postgrey let the mail pass, but after that Postfix is not able to locate the user (or dovecot not able to deliver the mail, i can't really tell):
postfix/smtpd: maps_find: local_recipient_maps: myuser: not found postfix/smtpd: dict_proxy_lookup: table=unix:passwd.byname flags=lock|utf8_request email@example.com -> status=1 result= postfix/smtpd: maps_find: local_recipient_maps: @mydomain.com: not found postfix/smtpd: mail_addr_find: firstname.lastname@example.org -> (not found) postfix/smtpd: NOQUEUE: reject: RCPT from senderdomain.de[185.26.XX.XX]: 550 5.1.1 <email@example.com>: Recipient address rejected: User unknown in local recipient table; from=<firstname.lastname@example.org> to=<email@example.com> proto=ESMTP helo=<senderdomain.de> postfix/smtpd: > senderdomain.de[185.26.XX.XX]: 550 5.1.1 <firstname.lastname@example.org>: Recipient address rejected: User unknown in local recipient table
If I run
postmap -s btree:/var/lib/postfix/verify_cache, however, I get the result
_LAST_CACHE_CLEANUP_COMPLETED_ 1552662532 email@example.com 0:0:1552662532:250 2.1.5 OK
so I assume the recipient validation works properly. Also, the correct maildir gets created in
Where can I look for further information why the mail delivery fails?
Thank you very much in advance.
I updated my LDAP configuration for the
local_recipient_maps, the search query is
query_filter = (rspfMail=%s) where
rspfMail is the attribute in which the users mail is stored.
When I test the query with
postmap -vq 'firstname.lastname@example.org' ldap:/etc/postfix/local_recipient_maps.cf I get:
postmap: dict_ldap_connect: Successful bind to server ldap://192.168.**.**:389 with dn cn=**,ou=**,dc=** postmap: dict_ldap_connect: Cached connection handle for LDAP source /etc/postfix/local_recipient_maps.cf postmap: dict_ldap_lookup: /etc/postfix/local_recipient_maps.cf: Searching with filter (rspfMailemail@example.com) postmap: dict_ldap_get_values: Search found 1 match(es) postmap: dict_ldap_get_values: Leaving dict_ldap_get_values postmap: dict_ldap_lookup: Search returned nothing
So the search finds exactly one result, as expected, but returns nothing. I would really appreciate any help.