Issue Cannot get OpenDKIM to run on Ubuntu 20.04, keep getting socket error!

[zoldos]

Server operating system version

Ubuntu 20.04

Plesk version and microupdate number

Plesk Obsidian 18.0.69 Update #3 Web Pro Edition

I'm trying to get OpenDKIM running on my dedicated Ubuntu 20.04 server. I got it working briefly, then I messed something up. Here are the logs and more details:

May 06 14:51:28 condor2388 opendkim[2800874]: opendkim: /etc/opendkim.conf: /etc/opendkim/TrustedHosts: dkimf_db_open(): No such file or directory
May 06 14:51:28 condor2388 systemd[1]: opendkim.service: Control process exited, code=exited, status=78/CONFIG
May 06 14:51:28 condor2388 systemd[1]: opendkim.service: Failed with result 'exit-code'.
May 06 14:51:28 condor2388 systemd[1]: Failed to start OpenDKIM DomainKeys Identified Mail (DKIM) Milter.
----
systemctl status opendkim.service:

opendkim.service - OpenDKIM DomainKeys Identified Mail (DKIM) Milter
     Loaded: loaded (/lib/systemd/system/opendkim.service; enabled; vendor preset: enabled)
     Active: failed (Result: exit-code) since Fri 2025-05-09 17:43:54 CDT; 17s ago
       Docs: man:opendkim(8)
             man:opendkim.conf(5)
             man:opendkim-genkey(8)
             man:opendkim-genzone(8)
             man:opendkim-testadsp(8)
             man:opendkim-testkey
             http://www.opendkim.org/docs.html
Process: 332658 ExecStart=/usr/sbin/opendkim -x /etc/opendkim.conf (code=exited, status=78)

May 09 17:43:54 condor2388 systemd[1]: opendkim.service: Scheduled restart job, restart counter is at 5.
May 09 17:43:54 condor2388 systemd[1]: Stopped OpenDKIM DomainKeys Identified Mail (DKIM) Milter.
May 09 17:43:54 condor2388 systemd[1]: opendkim.service: Start request repeated too quickly.
May 09 17:43:54 condor2388 systemd[1]: opendkim.service: Failed with result 'exit-code'.
May 09 17:43:54 condor2388 systemd[1]: Failed to start OpenDKIM DomainKeys Identified Mail (DKIM) Milter.

All paths are correct, all files exist with correct permissions and groups. I just can't get it to work. I think it's a socket error. Here is my Opendkim.conf file:

Domain                 bloodofsouls.com
Mode                   sv
KeyFile                /etc/opendkim/keys/bloodofsouls.com/default.private
Selector               default
Umask                  002
UserID                 opendkim:opendkim
KeyTable               /etc/opendkim/KeyTable
SigningTable           /etc/opendkim/SigningTable
ExternalIgnoreList     /etc/opendkim/TrustedHosts
InternalHosts          /etc/opendkim/TrustedHosts
PidFile                /run/opendkim/opendkim.pid
OversignHeaders        From
# Milter configuration
MilterProtocol         6
MilterSocket           local:/var/spool/postfix/opendkim/opendkim.sock
MilterSocketGroup      postfix
MilterSocketMode       660

It keeps saying config error on one specific line: MilterSocket, and I just can't get OpenDKIM to initialize.

I went in circles with a coding A.I. for 2 days, I guess I should have stopped when it was working, but then I had another error.

Can anyone help? My server's sent e-mails *are* being delivered, they just aren't being signed. SPF passes, and DMARC passes.

Thanks!!

 

[scsa20]

Why not just use the DKIM built into Plesk? If you really want to use OpenDKIM instead of what's built into Plesk, then you'll probably want to check out Resolved - Connecting OpenDKIM and Milter configuration on Plesk Obsidian as that user outline the process for getting it to work properly.

 

[zoldos]

Why not just use the DKIM built into Plesk? If you really want to use OpenDKIM instead of what's built into Plesk, then you'll probably want to check out Resolved - Connecting OpenDKIM and Milter configuration on Plesk Obsidian as that user outline the process for getting it to work properly.

There are multiple domains/sites on my server. Will the built in DKIM work for just *my* site? I don't want to interfere with the other domains since they aren't mine. I'm the server admin tho.

 

[zoldos]

@scsa20 Okay, I switched to the internal Plesk DKIM on my specific domain. I did everything carefully. I confirmed DKIM signing was enabled, etc. But for some reason, the default.pub key and dkim.sock files were *not* being created. I tried everything, and went back and forth with several so called "advanced" A.I. models. I spent at least 3 to 4 solid days working with it. No matter what I did, I can never get the "dkim.sock" file to generate. I restarted all sorts of things like postfix, dovecot, etc., etc. Changed the milter settings, updated main.conf, updated this, changed that, but nothing, it never creates this "socket" which is apparently a very important part of the DKIM system. And no matter what I did, I could not get Plesk to create the default.pub file. I finally did it manually, again via A.I. assistance, and added this to my DNS (with the correct syntax), and it matched the private key. It definitely propagated. But like I said, the socket still wasn't being generated, and nothing I did would ever get my server's sent e-mails to be DKIM signed.

I'm dome with the A.I. for now. You seem like a human ( ), can you offer any suggestions? I have no idea what could be wrong. Oh, and I completely removed OpenDkim so I know that isn't interfering.

Or if anyone else wants to offer help, I'm listening.

My e-mails *are* being delivered without issue to Outlook, Gmail, Yahoo, and others, but this issue is for some reason really bothering me. lol

Thanks!!

 

[Kaspar]

Or if anyone else wants to offer help, I'm listening.

Unfortunately I don't have any suggestions to solve the issue you're facing. However, since you mentioned that you've already been working on this issue for a number of days without any success, I do want to point out that if need technical assistance, there is always the option to open a support ticket with Plesk. They are usually a big help in solving any Plesk related technical problem and can investigate the issue directly on your server (if you allow them access).

 

[zoldos]

Unfortunately I don't have any suggestions to solve the issue you're facing. However, since you mentioned that you've already been working on this issue for a number of days without any success, I do want to point out that if need technical assistance, there is always the option to open a support ticket with Plesk. They are usually a big help in solving any Plesk related technical problem and can investigate the issue directly on your server (if you allow them access).

I was able to open a support ticket. Thank you so much!!