I am trying to setup an DKIM email signing for a postfix SMTP server.
This server is to be used by different services on the local network.
I have generated DKIM key pair, added it to my domain and was able to successfully send emails out from the server itself as seen here:
me@server:~$ telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 server.lan ESMTP Postfix (Ubuntu)
HELO example.com
250 server.lan
MAIL FROM: [email protected]
250 2.1.0 Ok
RCPT TO: [email protected]
250 2.1.5 Ok
DATA
354 End data with <CR><LF>.<CR><LF>
To:[email protected]
Subject:Testing from server
hello
.
250 2.0.0 Ok: queued as AAD604EA1CC2
That message is received with the correct DKIM signature.
But, if I do the exact same (only with telnet server.lan 25
) thing on another machine on the local network, the DKIM signature is not included and the recipient doesn't know who sent the email.
I have found that this entry in /var/log/mail.log
is relevant to it:
Jul 30 04:28:16 server opendkim[25664]: AAD604EA1CC2: can't determine message sender; accepting
So I have figured that postfix is not setting the FROM
address properly. So why is it not doing it and how can I fix it?
Thanks in advance...
The entire log during transaction from the workstation is this:
Jul 30 15:56:29 server postfix/smtpd[6795]: warning: database /etc/aliases.db is older than source file /etc/aliases
Jul 30 15:56:29 server postfix/smtpd[6795]: connect from workstation.lan[192.168.1.63]
Jul 30 15:57:24 server postfix/smtpd[6795]: 2C35E4EA1DD1: client=workstation.lan[192.168.1.63]
Jul 30 15:58:18 server postfix/cleanup[6799]: 2C35E4EA1DD1: message-id=<>
Jul 30 15:58:18 server opendkim[25664]: 2C35E4EA1DD1: can't determine message sender; accepting
Jul 30 15:58:18 server postfix/qmgr[25810]: 2C35E4EA1DD1: from=<[email protected]>, size=272, nrcpt=1 (queue active)
Jul 30 15:58:19 server postfix/smtp[6802]: 2C35E4EA1DD1: to=<[email protected]>, relay=ASPMX.L.GOOGLE.COM[173.194.70.26]:25, delay=67, delays=66/0.02/0.26/1.1, dsn=2.0.0, status=sent (250 2.0.0 OK 1343656739 a59si1127667wel.70)
Jul 30 15:58:19 server postfix/qmgr[25810]: 2C35E4EA1DD1: removed