> -----Original Message----- > From: Viktor Dukhovni via Postfix-users <[email protected]> > Sent: Monday, March 23, 2026 1:34 AM > To: [email protected] > Subject: [pfx] Re: Sender Domain Configuration Help > > On Sun, Mar 22, 2026 at 07:33:15PM -0400, Scott Hollenbeck via Postfix- > users wrote: > > I'm setting up a new server running Ubuntu 24.04.4 LTS and postfix 3.8.6. > > I'm having trouble getting postfix properly configured to send email from > > the server's domain name (dnsmon.net). As currently configured, email is > > identified as being sent from the server's host name (juno). This is what I > > see in the headers of a received message: > > > > Return-Path: <sah62@juno> > > From: Scott Hollenbeck <sah62@juno> > > > > Here are the configuration values returned from "postconf -n": > > > > myhostname = dnsmon.net > > myorigin = /etc/mailname > > > > ...and a few other relevant values: > > > > $ cat /etc/mailname > > dnsmon.net > > > > $ cat /etc/hostname > > juno > > > > I don't yet have a valid PTR record set for this new server. Could that be > > the problem? Is there something else I'm missing? > > Please see: https://www.postfix.org/DEBUG_README.html#mail > In particular, the above post lacks: > > - A clear, non-anecdotal report of the observed symptoms, [SAH] Thanks, I did read that before sending my original message. I provided the problem statement above. I'm trying to configure postfix so that the domain part of the sender email address is "dnsmon.net". What's being used is "juno", the host name.
> - Some relevant log entries, [SAH] Here's the log information for a sent message: 2026-03-22T18:29:00.796297-04:00 localhost postfix/pickup[32729]: C241860603C3: uid=1000 from=<sah62@juno> 2026-03-22T18:29:00.806446-04:00 localhost opendmarc[13030]: ignoring connection from localhost 2026-03-22T18:29:00.806975-04:00 localhost postfix/cleanup[32857]: C241860603C3: message-id=<[email protected]> 2026-03-22T18:29:00.810504-04:00 localhost opendkim[27548]: C241860603C3: DKIM-Signature field added (s=default, d=dnsmon.net) 2026-03-22T18:29:00.811585-04:00 localhost postfix/qmgr[32730]: C241860603C3: from=<sah62@juno>, size=366, nrcpt=1 (queue active) 2026-03-22T18:29:06.499664-04:00 localhost postfix/smtp[32859]: C241860603C3: to=<[email protected]>, relay=musclecarresearch.net[173.255.237.114]:25, delay=5.7, delays=0.04/0.02/5.5/0.22, dsn=4.2.0, status=deferred (host musclecarresearch.net[173.255.237.114] said: 450 4.2.0 <[email protected]>: Recipient address rejected: Greylisted, see https://postgrey.schweikert.ch/help/musclecarresearch.net.html (in reply to RCPT TO command)) 2026-03-22T18:36:30.707988-04:00 localhost postfix/qmgr[32730]: C241860603C3: from=<sah62@juno>, size=366, nrcpt=1 (queue active) 2026-03-22T18:36:31.493929-04:00 localhost postfix/smtp[33082]: C241860603C3: to=<[email protected]>, relay=musclecarresearch.net[173.255.237.114]:25, delay=451, delays=450/0.03/0.39/0.36, dsn=2.0.0, status=sent (250 2.0.0 Ok: queued as 42F243F008C) 2026-03-22T18:36:31.494102-04:00 localhost postfix/qmgr[32730]: C241860603C3: removed > - Full configuration details (postconf -nf, postconf -Mf) [SAH] postconf -nf: alias_database = hash:/etc/aliases alias_maps = hash:/etc/aliases append_dot_mydomain = no biff = no compatibility_level = 2 delay_warning_time = 4h disable_vrfy_command = yes dovecot_destination_recipient_limit = 1 header_checks = pcre:/etc/postfix/header_checks home_mailbox = Maildir/ inet_protocols = ipv4 mailbox_command = /usr/bin/procmail -a $EXTENSION mailbox_size_limit = 0 message_size_limit = 20480000 milter_default_action = accept milter_protocol = 6 mydestination = $myhostname, localhost.localdomain, localhost, juno myhostname = dnsmon.net mynetworks = 127.0.0.0/8 192.168.0.0/16 96.231.245.36 [::ffff:127.0.0.0]/104 [::1]/128 173.255.237.114 [2600:3c03::]/64 myorigin = /etc/mailname non_smtpd_milters = $smtpd_milters policyd-spf_time_limit = 3600 postscreen_access_list = permit_mynetworks,cidr:/etc/postfix/postscreen_access.cidr postscreen_blacklist_action = drop postscreen_dnsbl_action = enforce postscreen_dnsbl_reply_map = texthash:/etc/postfix/postscreen_dnsbl_reply postscreen_dnsbl_sites = zen.spamhaus.org*3 b.barracudacentral.org*2 bl.spameatingmonkey.net*2 bl.spamcop.net dnsbl.sorbs.net psbl.surriel.com bl.mailspike.net swl.spamhaus.org*-4 list.dnswl.org=127.[0..255].[0..255].0*-2 list.dnswl.org=127.[0..255].[0..255].1*-3 list.dnswl.org=127.[0..255].[0..255].[2..255]*-4 postscreen_dnsbl_threshold = 3 postscreen_greet_action = enforce readme_directory = no recipient_delimiter = + smtp_tls_security_level = may smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu) smtpd_client_restrictions = permit_mynetworks, reject_unauth_pipelining, reject_unknown_client_hostname, check_client_access cidr:/etc/postfix/blacklist_cidr, permit smtpd_milters = local:opendkim/opendkim.sock,local:opendmarc/opendmarc.sock smtpd_recipient_restrictions = reject_unauth_pipelining, reject_non_fqdn_recipient, reject_unknown_recipient_domain, permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination, check_policy_service unix:private/policyd-spf, check_policy_service inet:127.0.0.1:10023, permit smtpd_relay_restrictions = permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination smtpd_sasl_auth_enable = yes smtpd_sasl_path = private/auth-client smtpd_sasl_security_options = noanonymous smtpd_sasl_type = dovecot smtpd_sender_restrictions = permit_mynetworks, check_sender_access hash:/etc/postfix/blacklist_hash, check_sender_access pcre:/etc/postfix/blacklist.pcre, permit smtpd_tls_cert_file = /etc/letsencrypt/live/dnsmon.net/fullchain.pem smtpd_tls_ciphers = high smtpd_tls_dh1024_param_file = /etc/ssl/private/dh2048.pem smtpd_tls_dh512_param_file = /etc/ssl/private/dh512.pem smtpd_tls_key_file = /etc/letsencrypt/live/dnsmon.net/privkey.pem smtpd_tls_mandatory_ciphers = high smtpd_tls_mandatory_protocols = >=TLSv1.2, <=TLSv1.3 smtpd_tls_protocols = >=TLSv1.2, <=TLSv1.3 smtpd_tls_security_level = may smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache tls_high_cipherlist = HIGH:!aNULL:!MD5 tls_preempt_cipherlist = yes virtual_alias_maps = hash:/etc/postfix/virtual virtual_gid_maps = static:5000 virtual_mailbox_base = /home/vmail virtual_mailbox_domains = /etc/postfix/vhosts virtual_mailbox_maps = hash:/etc/postfix/vmaps virtual_minimum_uid = 1000 virtual_uid_maps = static:5000 postconf -Mf: smtp inet n - y - - smtpd smtpd pass - - y - - smtpd -o content_filter=spamassassin dnsblog unix - - y - 0 dnsblog tlsproxy unix - - y - 0 tlsproxy submission inet n - y - - smtpd -o syslog_name=postfix/submission -o smtpd_tls_security_level=encrypt -o smtpd_sasl_auth_enable=yes -o smtpd_client_restrictions=permit_sasl_authenticated,reject pickup fifo n - y 60 1 pickup cleanup unix n - y - 0 cleanup qmgr unix n - n 300 1 qmgr tlsmgr unix - - y 1000? 1 tlsmgr rewrite unix - - y - - trivial-rewrite bounce unix - - y - 0 bounce defer unix - - y - 0 bounce trace unix - - y - 0 bounce verify unix - - y - 1 verify flush unix n - y 1000? 0 flush proxymap unix - - n - - proxymap proxywrite unix - - n - 1 proxymap smtp unix - - y - - smtp relay unix - - y - - smtp showq unix n - y - - showq error unix - - y - - error retry unix - - y - - error discard unix - - y - - discard local unix - n n - - local virtual unix - n n - - virtual lmtp unix - - y - - lmtp anvil unix - - y - 1 anvil scache unix - - y - 1 scache postlog unix-dgram n - n - 1 postlogd maildrop unix - n n - - pipe flags=DRhu user=vmail argv=/usr/bin/maildrop -d ${recipient} uucp unix - n n - - pipe flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient) ifmail unix - n n - - pipe flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient) bsmtp unix - n n - - pipe flags=Fq. user=bsmtp argv=/usr/lib/bsmtp/bsmtp -t$nexthop -f$sender $recipient scalemail-backend unix - n n - 2 pipe flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store ${nexthop} ${user} ${extension} mailman unix - n n - - pipe flags=FRX user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py ${nexthop} ${user} dovecot unix - n n - - pipe flags=DRhu user=vmail:vmail argv=/usr/lib/dovecot/deliver -f ${sender} -d ${recipient} scan unix - - n - 16 smtp -o smtp_send_xforward_command=yes 127.0.0.1:10026 inet n - n - 16 smtpd -o content_filter= -o receive_override_options=no_unknown_recipient_checks,no_header_body_checks -o smtpd_helo_restrictions= -o smtpd_client_restrictions= -o smtpd_sender_restrictions= -o smtpd_recipient_restrictions=permit_mynetworks,reject -o mynetworks_style=host -o smtpd_authorized_xforward_hosts=127.0.0.0/8 spamassassin unix - n n - - pipe user=debian-spamd argv=/usr/bin/spamc -f -e /usr/sbin/sendmail -oi -f ${sender} ${recipient} policyd-spf unix - n n - 0 spawn user=policyd-spf argv=/usr/bin/policyd-spf I hope this helps. Scott _______________________________________________ Postfix-users mailing list -- [email protected] To unsubscribe send an email to [email protected]
