5

Have been struggling for a day already and can't find solution. When try to send mails to some hosts:

Jan  5 10:31:37 vps**** sm-mta[2192]: STARTTLS=client, relay=mail-x.*****.co.uk., version=TLSv1/SSLv3, verify=FAIL, cipher=DHE-RSA-AES256-SHA, bits=256/256
Jan  5 10:31:37 vps**** sm-mta[2192]: u059Vb4d002190: to=<****@****.co.uk>, ctladdr=<root@vps****.ovh.net> (0/0), delay=00:00:00, xdelay=00:00:00, mailer=esmtp, pri=124764, relay=mail-x.****.co.uk. [212.46.138.29], dsn=5.1.8, stat=Service unavailable

After some study found that it might be TLS problem so tried to disable and add:

Try_TLS:   NO

but then I get:

Jan  5 10:33:56 vps**** sm-mta[2375]: ruleset=try_tls, arg1=mail-x.****.co.uk, relay=mail-x.****.co.uk, reject=550 5.7.1 <****@****.co.uk>... do not try TLS with mail-x.****.co.uk [212.46.138.29]
Jan  5 10:33:56 vps**** sm-mta[2375]: u059XuVY002373: to=<****@****.co.uk>, ctladdr=<root@vps****.ovh.net> (0/0), delay=00:00:00, xdelay=00:00:00, mailer=esmtp, pri=124764, relay=mail-x.****.co.uk. [212.46.138.29], dsn=5.1.8, stat=Service unavailable

My sendmail version and settings: 8.14.4 on Ubuntu

============ SYSTEM IDENTITY (after readcf) ============
(short domain name) $w = vps****
(canonical domain name) $j = vps****.ovh.net
(subdomain name) $m = ovh.net
(node name) $k = vps****.ovh.net
========================================================

Any ideas?

Additional info:

Sending a test message in verbose mode generated the following error:

554 5.1.8 : Sender address rejected: MX record not found

AnFi
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Amundio
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1 Answers1

6

Sendmail: Debugging outgoing SMTP session

As root send a test message with full tracking of the SMTP session.
Usually it provides some useful hints. 

#!/bin/sh

RECIPIENT='****@****.co.uk'

# -i  : sendmail will rewrite lines starting with dot
# -Am : use sendmail.cf instead of submit.cf (usually requires root privileges) 
# -v  : use verbose mode (track SMTP session to STDERR)
# --  : separate command line arguments and recipients list
/usr/sbin/sendmail -i -Am -v -- $RECIPIENT <<END
Subject: test message
To: $RECIPIENT

test message body   
END

sendmail.sendmail(8) - man page

AnFi
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  • Thank you, I get: 250 2.1.0 Ok >>> RCPT To:<****@****.co.uk> >>> DATA 554 5.1.8 : Sender address rejected: MX record not found 554 5.5.1 Error: no valid recipients Postfix sends e-mails to this host without a problem. – Amundio Jan 05 '16 at 13:02
  • It seems that remove mail sender rejects your envelope sender (as used `MAIL FROM:`) because the sender domain does not have an `MX` DNS record. Is your serveer based on static IP address? – AnFi Jan 05 '16 at 13:26
  • Yes, it was the case, had to change the envelope and worked like a charm. – Amundio Jan 05 '16 at 13:43
  • Do you want to fix TLS problem too? It is most likely caused by self-signed certificate. Making your sendmail check MD5 checksum of the certificate may be a good way to fix it. – AnFi Jan 05 '16 at 14:00
  • Thank you Andrzej. Yes it's due to self signed certificate. Will try to do the MD5 checksum. Any hints on it? Is it an option in the config? – Amundio Jan 06 '16 at 12:01
  • AFAIR I have seen somewhere purely sendmail.mc/sendmail.cf (configuration files) implementation of accepting SSL certificate based on MD5 checksum. AFAIR it gave quite good **first impression**. You may ask at news:comp.mail.sendmail for the link and the reviews. – AnFi Jan 06 '16 at 12:21