i am about 2 hours on configure dkim with postfix on ubuntu 20.04. I try absolutly everything, but dkim wont work.
OpenDKIM-Service won´t start:
root@mail:~# service opendkim status
● opendkim.service - OpenDKIM DomainKeys Identified Mail (DKIM) Milter
Loaded: loaded (/lib/systemd/system/opendkim.service; enabled; vendor preset: enabled)
Active: activating (start) since Sat 2022-01-08 19:39:15 CET; 59s ago
Docs: man:opendkim(8)
man:opendkim.conf(5)
man:opendkim-genkey(8)
man:opendkim-genzone(8)
man:opendkim-testadsp(8)
man:opendkim-testkey
http://www.opendkim.org/docs.html
Process: 62335 ExecStart=/usr/sbin/opendkim -x /etc/opendkim.conf (code=exited, status=0/SUCCESS)
Tasks: 7 (limit: 19660)
Memory: 2.7M
CGroup: /system.slice/opendkim.service
├─62336 /usr/sbin/opendkim -x /etc/opendkim.conf
└─62337 /usr/sbin/opendkim -x /etc/opendkim.conf
Jan 08 19:39:15 mail.mydomain.de systemd[1]: Starting OpenDKIM DomainKeys Identified Mail (DKIM) Milter...
Jan 08 19:39:15 mail.mydomain.de systemd[1]: opendkim.service: Can't open PID file /run/opendkim/opendkim.pid (yet?) after start: Operation not permitted
Jan 08 19:39:15 mail.mydomain.de opendkim[62337]: OpenDKIM Filter v2.11.0 starting (args: -x /etc/opendkim.conf)
Jan 07 13:32:59 mail.mydomain.de systemd[1]: Starting OpenDKIM DomainKeys Identified Mail (DKIM) Milter...
Jan 07 13:32:59 mail.mydomain.de systemd[1]: Started OpenDKIM DomainKeys Identified Mail (DKIM) Milter.
Jan 07 13:32:59 mail.mydomain.de opendkim[275965]: OpenDKIM Filter v2.11.0 starting (args: -x /etc/opendkim.conf)
Jan 08 10:35:44 mail.mydomain.de systemd[1]: Stopping OpenDKIM DomainKeys Identified Mail (DKIM) Milter...
Jan 08 10:35:50 mail.mydomain.de systemd[1]: opendkim.service: Succeeded.
Jan 08 10:35:50 mail.mydomain.de systemd[1]: Stopped OpenDKIM DomainKeys Identified Mail (DKIM) Milter.
Here is my /etc/opendkim.conf:
Syslog yes
UMask 002
Canonicalization simple
Mode sv
SubDomains no
AutoRestart yes
AutoRestartRate 10/1M
Background yes
DNSTimeout 5
SignatureAlgorithm rsa-sha256
OversignHeaders From
TrustAnchorFile /usr/share/dns/root.key
UserID opendkim
KeyTable refile:/etc/opendkim/key.table
SigningTable refile:/etc/opendkim/signing.table
ExternalIgnoreList /etc/opendkim/trusted.hosts
InternalHosts /etc/opendkim/trusted.hosts
Socket local:/var/spool/postfix/opendkim/opendkim.sock
Here is my /etc/default/opendkim.conf
SOCKET="local:/var/spool/postfix/opendkim/opendkim.sock"
Here is my master.cf:
smtp inet n - y - - smtpd
submission inet n - y - - smtpd
-o smtpd_enforce_tls=yes
-o smtpd_sasl_auth_enable=yes
-o smtpd_client_restrictions=permit_sasl_authenticated,reject
pickup unix 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
-o syslog_name=postfix/$service_name
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=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py
${nexthop} ${user}
smtps inet n - y - - smtpd
-o smtpd_tls_wrappermode=yes
Here is my /etc/postfix/main.cf:
smtpd_banner = $myhostname ESMTP
myhostname = mail.mydomain.de
biff = no
append_dot_mydomain = no
readme_directory = no
compatibility_level = 2
message_size_limit = 10240000
smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
smtpd_tls_security_level=may
smtp_tls_CApath=/etc/ssl/certs
smtp_tls_security_level=may
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
smtpd_recipient_restrictions = permit_mynetworks, reject_unauth_destination, reject_non_fqdn_sender
milter_default_action = accept
milter_protocol = 6
smtpd_milters = local:opendkim/opendkim.sock
non_smtpd_milters = $smtpd_milters
smtpd_sender_restrictions = permit_mynetworks, permit_sasl_authenticated
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = localhost
relayhost =
smtpd_relay_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination
mailbox_command = procmail -a "$EXTENSION"
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
inet_protocols = all
virtual_alias_maps = hash:/etc/postfix/virtual
virtual_mailbox_maps = mysql:/etc/postfix/mysql-users.cf
virtual_transport = lmtp:[localhost]:2003
virtual_mailbox_domains = mydomain1.de, mydomain2.de
smtpd_tls_ciphers = medium
smtpd_tls_mandatory_ciphers = medium
tls_medium_cipherlist = ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384
smtpd_tls_mandatory_protocols = TLSv1.2
smtpd_tls_protocols = TLSv1.2
smtpd_tls_security_level = may
smtp_tls_security_level = may
smtp_use_tls = no
smtpd_client_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_rbl_client zen.spamhaus.org
smtp_send_xforward_command = yes
smtpd_authorized_xforward_hosts = 127.0.0.0/8 [::1]/128
smtpd_sasl_auth_enable = no
virtual_mailbox_base = /var/qmail/mailnames
virtual_uid_maps = static:30
virtual_gid_maps = static:31