Mailing List Archive

A month ago I upgraded to Exim version 4.94.2 #2 built 03-Jul-2022
03:34:43 - after figuring out how to fix my Tainted issues. I didn't
change any other parameters. This server is used to relay out from my
customers to the rest of the world (machine = relay.vweb.co.za).

Tainted areas were about using the correct DKIM signature according to
the customer so all changes were made in...

remote_smtp:
    driver = smtp
    dnssec_request_domains = *
    hosts_try_dane = *
    return_path = ${address:$reply_address}
    dkim_domain = ${lookup mysql {select domain from admin WHERE
domain='${domain:$h_from:}' limit 1}}
    dkim_selector = ${substr_2_4:$tod_zulu}
    dkim_private_key = ${if
exists{/etc/exim/dkim/$dkim_domain-$dkim_selector.pem}{/etc/exim/dkim/$dkim_domain-$dkim_selector.pem}{0}}
    dkim_canon=relaxed

My users (and thus all their domain names) are in a MySQL Database.
My DKIM files are updated once a month - hence the "$tod_zulu" parts...

Contents of /etc/exim/dkim/ contain the DKIM files for a few hundred
domains...

jpfa.co.za-2207.pem
jpfa.co.za-2207.pub
jpfa.co.za-2208.pem
jpfa.co.za-2208.pub

... so the "2207" (July 2022) files will get removed in a day or two...

Thought folk might like to see what I did to help them solve their
mastery of DKIM signing per Domain (or tell me what would work better).

Now, My Problem:-

Now I see more and more undeliverable emails not being returned to their
sender. This didn't happen before. Any clues as to where to look? If an
email is undeliverable after a week - they should be returned to sender.

relay /var/spool/exim/input # ls -l
total 9760
-rw-r----- 1 mail mail  213385 Jul 15 07:56 1oCEJm-00D32g-Gq-D
-rw-r----- 1 mail mail    3522 Jul 30 08:01 1oCEJm-00D32g-Gq-H
-rw-r----- 1 mail mail  112777 Jul 15 08:41 1oCF1F-00D3LG-6C-D
-rw-r----- 1 mail mail    3687 Jul 30 08:44 1oCF1F-00D3LG-6C-H
-rw-r----- 1 mail mail   31875 Jul 19 08:42 1oDgw4-00Ehut-4f-D
-rw-r----- 1 mail mail    3608 Jul 30 08:44 1oDgw4-00Ehut-4f-H
-rw-r----- 1 mail mail       0 Aug  2 16:59 1oDgw4-00Ehut-4f-J
-rw-r----- 1 mail mail   31331 Jul 18 14:54 1oDQGE-00EUsC-An-D
-rw-r----- 1 mail mail     969 Aug  2 15:08 1oDQGE-00EUsC-An-H
-rw-r----- 1 mail mail  175065 Jul 20 15:16 1oE9YY-00FCQn-VN-D
-rw-r----- 1 mail mail    3664 Jul 31 15:27 1oE9YY-00FCQn-VN-H
-rw-r----- 1 mail mail     112 Jul 22 12:59 1oEqNs-00FeP3-JI-D
-rw-r----- 1 mail mail    3636 Aug  2 13:02 1oEqNs-00FeP3-JI-H
-rw-r----- 1 mail mail    2240 Jul 21 10:40 1oERje-00FS4Y-9o-D
-rw-r----- 1 mail mail    3818 Aug  1 10:42 1oERje-00FS4Y-9o-H
-rw-r----- 1 mail mail  409222 Jul 27 12:57 1oGej7-00GfSF-PZ-D
-rw-r----- 1 mail mail    3988 Jul 30 13:20 1oGej7-00GfSF-PZ-H
-rw-r----- 1 mail mail  409226 Jul 27 13:00 1oGemN-00GfSF-66-D
-rw-r----- 1 mail mail    3952 Jul 30 13:03 1oGemN-00GfSF-66-H
-rw-r----- 1 mail mail  409224 Jul 27 12:41 1oGeTP-00GfSF-CL-D
-rw-r----- 1 mail mail    3973 Jul 30 12:48 1oGeTP-00GfSF-CL-H
-rw-r----- 1 mail mail  409225 Jul 27 12:45 1oGeXK-00GfSF-Rq-D
-rw-r----- 1 mail mail    3934 Jul 30 12:51 1oGeXK-00GfSF-Rq-H
-rw-r----- 1 mail mail    1728 Jul 27 16:24 1oGhxg-00Gja7-4n-D
-rw-r----- 1 mail mail    3635 Jul 30 16:25 1oGhxg-00Gja7-4n-H
-rw-r----- 1 mail mail 5100550 Jul 26 18:25 1oGNMx-00GSKI-HX-D
-rw-r----- 1 mail mail    3640 Jul 29 18:25 1oGNMx-00GSKI-HX-H
-rw-r----- 1 mail mail   33013 Jul 28 08:24 1oGwx8-00HE0Z-ED-D
-rw-r----- 1 mail mail    3531 Jul 31 08:29 1oGwx8-00HE0Z-ED-H

[newer files not shown]

I also don't like how some "headers" are much newer than the Data files
- unless they are being updated as and when a partial delivery (multiple
recipients) is made - though most of the above are to a single recipient.

I also deleted an even older bunch of "Headers only" ( -H suffixed
files) - which confuses me. Is EXIM forgetting to completely clean up
after itself?

--

Mark James ELKINS  -  Posix Systems - (South) Africa
mje@posix.co.za       Tel: +27.826010496 <tel:+27826010496>
For fast, reliable, low cost Internet in ZA: https://ftth.posix.co.za
<https://ftth.posix.co.za>