The desired settings are to create a multi domain mail server.
This is my main domain example.com and this is my subdomain: mail.example.com
Taking the rDNS as the following verifications:
hostname -f
nano /etc/mailname
nano /etc/hostname
As a result:
mail.example.com
I already have the DNS records in (TXT Record):
1 record txt: @ v=spf1 a mx ip4:170.000.100.16 ~all
2 record txt: _dmarc.mail v=DMARC1; p=none
3 record txt: mail v=spf1 a mx ip4:170.000.100.16 ~all
4 record txt: mail._domainkey v=DKIM1; h=sha256; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA6yQ4ZdFGg1/rjh8MbYYTGm00n...
I have made the following configuration in: nano /etc/opendkim.conf
AutoRestart Yes
AutoRestartRate 10/1h
Syslog yes
SyslogSuccess yes
LogWhy yes
Canonicalization relaxed/simple
Mode sv
SubDomains yes
#OversignHeaders From
SignHeaders From,Sender,To,CC,Subject,Message-Id,Date
OversignHeaders From,Sender,To,CC,Subject,Message-Id,Date
UserID opendkim:opendkim
UMask 002
Socket inet:8891@localhost
PidFile /var/run/opendkim/opendkim.pid
SignatureAlgorithm rsa-sha256
TrustAnchorFile /usr/share/dns/root.key
#Nameservers 127.0.0.1
Nameservers 8.8.8.8,1.1.1.1
ExternalIgnoreList refile:/etc/opendkim/TrustedHosts
InternalHosts refile:/etc/opendkim/TrustedHosts
KeyTable /etc/opendkim/KeyTable
SigningTable refile:/etc/opendkim/SigningTable
And, in the file /etc/default/opendkim I have the following:
RUNDIR=/run/opendkim
#SOCKET=local:$RUNDIR/opendkim.sock
SOCKET="local:/var/spool/postfix/opendkim/opendkim.sock"
USER=opendkim
GROUP=opendkim
PIDFILE=$RUNDIR/$NAME.pid
EXTRAAFTER=
Configured KeyTable, SigningTable and TrustedHosts files:
KeyTable:
mail._domainkey.example.com example.com:mail:/etc/opendkim/keys/example.com/mail.private
mail._domainkey.mail.example.com mail.example.com:mail:/etc/opendkim/keys/mail.example.com/mail.private
SigningTable:
*@example.com mail._domainkey.example.com
TrustedHosts:
127.0.0.1
::1
170.000.100.16
2100:1c02::f03c:13ff:fec9:17c7
mail.example.com
example.com
And the postfix configuration in: /etc/postfix/main.cf
smtpd_milters = inet:127.0.0.1:8891
non_smtpd_milters = $smtpd_milters
milter_default_action = accept
Finally I comment the versions that I have installed on my server:
postconf mail_version
mail_version = 3.5.13
lsb_release -d
Description: Debian GNU/Linux 11 (bullseye)
I have not been able to check the version of opendkim --version, but the installation was done this week, so I must have the most current version.
Tools I have used:
I can send and receive emails without problems, the only detail is that it does not show me in the emails sent that they are being signed with OpenDKIM, in addition to the screenshots that show those errors.
