Hello,
I read the “Postfix ETRN Howto” [1] as well as man 5 postconf with regards to:
postscreen_discard_ehlo_keywords
smtpd_discard_ehlo_keywords
... and disabled the announcement of ETRN via:
postscreen_discard_ehlo_keywords = ETRN
smtpd_discard_ehlo_keywords = ETRN
I then restarted the server and observed an inbound connection from Gmail:
Feb 27 21:12:19 server postfix/smtpd[2369]: connect from
mail-oi0-x22f.google.com
Feb 27 21:12:19 server postfix/smtpd[2369]: discarding EHLO keywords: ETRN
Feb 27 21:12:19 server postfix/smtpd[2369]: Trusted TLS connection established
...
Feb 27 21:12:19 server postfix/smtpd[2369]: discarding EHLO keywords: ETRN
My question is:
** Is the Gmail SMTP server attempting to use ETRN on the first, unencrypted
SMTP session with my server and then attempting to request it again after
STARTTLS when the TLS connection is established and this is why it is logging
that it is discarding ETRN each time or ...
** Is Postfix logging that ETRN is disabled on the first, unencrypted SMTP
session and then logging this again for the encrypted session (ie: Postfix is
just logging I disabled this and Google is not attempting to issue ETRN each
time) ?
Thanks,
- J
Sources:
[1] www.postfix.org/ETRN_README.html
