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Old 6th August 2008
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jggimi jggimi is offline
More noise than signal
 
Join Date: May 2008
Location: USA
Posts: 7,975
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Sendmail appears to be running, and it appears outgoing transmissions may be blocked.

In OpenBSD, the default configuration for sendmail is described in the afterboot(8) man page, recommended by the "Welcome to OpenBSD" letter in /var/mail/root. It says:
Quote:
OpenBSD ships with a default /etc/mail/localhost.cf file that will work
for simple installations; it was generated from openbsd-localhost.mc in
/usr/share/sendmail/cf. Please see /usr/share/sendmail/README and
/usr/share/doc/smm/08.sendmailop/op.me for information on generating your
own sendmail configuration files. For the default installation, sendmail
is configured to only accept connections from the local host and to not
accept connections on any external interfaces. This makes it possible to
send mail locally, but not receive mail from remote servers, which is
ideal if you have one central incoming mail machine and several clients.
To cause sendmail to accept external network connections, modify the
sendmail_flags variable in /etc/rc.conf.local to use the
/etc/mail/sendmail.cf file in accordance with the comments therein. This
file was generated from openbsd-proto.mc.

Note that sendmail now also listens on port 587 by default. This is to
implement the RFC 2476 message submission protocol. You may disable this
via the no_default_msa option in your sendmail .mc file. See
/usr/share/sendmail/README for more information.
In order to participate in Internet mail, as milo wishes to do, his ISP must permit outgoing SMTP traffic, and the receiving Mail Transfer Agent must be willing to accept the traffic from milo's IP address. In today's e-mail world, neither of these will be certain. In current anti-spam practice, ISPs often block outbound SMTP traffic from non-commercial broadband and dial up customer pools, and, many MTAs use block lists to prevent inbound traffic from those pools, even if the ISPs permit the traffic.

Because the maillog does not show a REJECT, my assumption is blocked SMTP traffic.

A simple test is possible. I am behind a corporate firewall, so cannot use dig(1) to find the MX records for aise-informatique.com. So, milo, use dig:
$ dig aise-informatique MX (I can't run it to check, see the man page if this doesn't work for you.)
After obtaining the MTA(s) IP address(es), use telnet to prove or disprove a connection issue:
$ telnet <address> 25
is all that is needed. If milo gets "connection refused" or a hang with no connection at all, that would be a network block. If the connection completes, then there might be a sendmail configuration issue.

Last edited by jggimi; 6th August 2008 at 03:23 PM.
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