邮箱服务使用DKIM签名，但OpenDKIM无法启动，如何解决？

Question

邮箱服务已经可以正常使用，不过还缺dkim签名的部分，参考了以下文章进行安装。
https://blog.csdn.net/yetugeng/article/details/83996397

不过opendkim始终没有启动，导致发信时并未进行签名。
在mail.log中显示会产生相关报错

Aug  8 14:27:19 saikano postfix/smtpd[105588]: warning: connect to Milter service inet:127.0.0.1:8891: Connection refused

查看opendkim的运行状况则是

[root@saikano ~]# sudo service opendkim status
Redirecting to /bin/systemctl status opendkim.service
× opendkim.service - DomainKeys Identified Mail (DKIM) Milter
     Loaded: loaded (/usr/lib/systemd/system/opendkim.service; enabled; preset: disabled)
     Active: failed (Result: exit-code) since Tue 2023-08-08 15:29:23 CST; 1s ago
   Duration: 15ms
       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: 108304 ExecStart=/usr/sbin/opendkim -f $OPTIONS (code=exited, status=78)
   Main PID: 108304 (code=exited, status=78)
        CPU: 11ms

Aug 08 15:29:23 saikano.top systemd[1]: opendkim.service: Main process exited, code=exited, status=78/CONFIG
Aug 08 15:29:23 saikano.top systemd[1]: opendkim.service: Failed with result 'exit-code'.
Aug 08 15:29:23 saikano.top systemd[1]: opendkim.service: Scheduled restart job, restart counter is at 5.
Aug 08 15:29:23 saikano.top systemd[1]: Stopped DomainKeys Identified Mail (DKIM) Milter.
Aug 08 15:29:23 saikano.top systemd[1]: opendkim.service: Start request repeated too quickly.
Aug 08 15:29:23 saikano.top systemd[1]: opendkim.service: Failed with result 'exit-code'.
Aug 08 15:29:23 saikano.top systemd[1]: Failed to start DomainKeys Identified Mail (DKIM) Milter.

看运行状态的话一开始没有注意，它这边显示的是"saikano.top"这是我博客的域名，而我的邮箱服务并没有用这个域名，这两个都架设在同一个服务器，不知是否与该问题有关。

我也检查过一些地方，配置是否有写错，是否有权限问题，尽量检查修改了。

各位大神是否有办法呢！如果网络上有这方面的讲解或者这个问题的其他解法，请麻烦告诉我也可以节省时间重复回答。辛苦了！

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重新试了两次依然存在问题，第一次依旧参考原本的指南。第二次一切从简，并去除所有注释，先能跑通再说，参考 https://tm.root-n.com/tec:opendkim:setup

/etc/opendkim/opendkim.conf

Mode                    sv
Socket                  inet:8891@localhost
KeyTable                /etc/opendkim/KeyTable
SigningTable            refile:/etc/opendkim/SigningTable
ExternalIgnoreList      refile:/etc/opendkim/TrustedHosts
InternalHosts           refile:/etc/opendkim/TrustedHosts

/etc/opendkim/KeyTable

default._domainkey.###.com ###.com:default:/etc/opendkim/keys/###.com/default.private

/etc/opendkim/SigningTable

*@###.com default._domainkey.###.com

/etc/opendkim/TrustedHosts

127.0.0.1
::1

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找到了类似问题，同样报错为配置错误。
https://forum.virtualmin.com/t/dkim-setup-failed/117124/2

opendkim.service: Main process exited, code=exited, status=78/CONFIG

有回答建议使用 journalctl -u opendkim.service 查看原因，但是结果我很惊讶，文件不存在。

Aug 08 13:55:41 saikano.top systemd[1]: opendkim.service: Failed with result 'exit-code'.
Aug 08 13:55:41 saikano.top systemd[1]: opendkim.service: Scheduled restart job, restart counter is at 3.
Aug 08 13:55:41 saikano.top systemd[1]: Stopped DomainKeys Identified Mail (DKIM) Milter.
Aug 08 13:55:41 saikano.top systemd[1]: Started DomainKeys Identified Mail (DKIM) Milter.
Aug 08 13:55:41 saikano.top opendkim[103885]: /etc/opendkim/keys/default.private: open(): No such file or directory
Aug 08 13:55:41 saikano.top opendkim[103885]: opendkim: /etc/opendkim.conf: /etc/opendkim/keys/default.private: open(): No such file or directory
Aug 08 13:55:41 saikano.top systemd[1]: opendkim.service: Main process exited, code=exited, status=78/CONFIG

原先/etc/opendkim/KeyTable的配置是以下这样，按理来说不应该这样。

default._domainkey.###.com ###.com:default:/etc/opendkim/keys/###.com/default.private

后来修改为以下这样，并把秘钥放到/etc/opendkim/keys/default.private依旧不行。

default._domainkey.###.com ###.com:default:/etc/opendkim/keys/default.private

Answer 1

OpenDKIM配置文件/etc/opendkim.conf,配的路径对吗，还有权限，还有就是看一下日志
看下这个帖子：https://stackoverflow.com/questions/20778771/what-is-the-difference-between-0-0-0-0-127-0-0-1-and-localhost