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<p><font face="Verdana">Hello,</font></p>
<p><font face="Verdana">I'm using version 2.3.4.1 and I have a fairly simple setup based on a submission server where I run dovecot and a relay server with postfix. The relevant part of dovecot's config is as follows (sanitized):</font></p>
<p>hostname = submission.domain.local
submission_client_workarounds = whitespace-before-path
submission_relay_host = 192.168.1.1 <- postfix
submission_relay_port = 25
submission_relay_trusted = yes
</p>
<p>Postfix is configured as follows:</p>
<p>smtpd_authorized_xclient_hosts = 192.168.1.2 <- submission server</p>
<p>Everything apparently works as expected, meaning that I can correctly authenticate on the submission server and the email is relayed to postfix, where I can see the original MUA's IP correctly logged.</p>
<p>There is, however, a little problem with the client HELO string that is not being forwarded to postfix. Instead of having the MUA HELO, I see the submission server HELO, as shown in the following tcpdump taken on the postfix server:</p>
<p>220 postfix.domain.local ESMTP Postfix (Ubuntu)
EHLO submission.domain.local
250-postfix.domain.local
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-AUTH DIGEST-MD5 CRAM-MD5 NTLM PLAIN LOGIN
250-AUTH=DIGEST-MD5 CRAM-MD5 NTLM PLAIN LOGIN
250-XCLIENT NAME ADDR PROTO HELO REVERSE_NAME PORT LOGIN DESTADDR DESTPORT
250-ENHANCEDSTATUSCODES
250-8BITMIME
250-DSN
250 SMTPUTF8
XCLIENT ADDR=192.168.1.3 PORT=57116 LOGIN=riccardo-at-domain.local
220 postfix.domain.local ESMTP Postfix (Ubuntu)
EHLO submission.domain.local
250-postfix.domain.local
250-PIPELINING
...
</p>
<p>As you can see the first EHLO is correctly done with the submission server's hostname, but the subsequent one after XCLIENT is -still- the same hostname, while I was expecting that to be the one forwarded from the MUA, or possibly a "HELO=somethingelse" in the XCLIENT line.
</p>
<p>I've looked almost everywhere and I couldn't find a way to make dovecot use the MUA's HELO string. The question I'm asking is if there is a way to have the MUA's HELO forwarded to the relay server in some way, or if this is a bug or an expected behaviour.</p>
<p>Thanks for any help you could give
</p>
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<pre class="moz-signature" cols="72">--
Best regards,
Riccardo Alfieri
Spamhaus Technology
<a class="moz-txt-link-freetext" href="https://www.spamhaustech.com/">https://www.spamhaustech.com/</a></pre>
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