Here is a tool that will accept both manual DKIM data you may have, and the DKIM signatures generated by ISPCONFIG and feed them to an opendkim server you have on that machine.
Why do you want to install an OpenDkim server when Rspamd or Amavis has already done the DKIM signing?
Was thinking the same... And dkim settings in ISPC are implemented well in those packages. Absolutely no need to install anything else for dkim signing, which also won't be compatible with ISPC.
There is one thing that came to my mind after I read his other post where he mentioned sending 20k emails using mailman, so maybe its just some kind of mass mailing outgoing server solution. But maybe @Turgut Kalfaoglu will explain why he needs opendkim for his purpose.
Even then... I would expect mailman to send through postfix as MTA and with that use rspmd or amavis for signing.
I have a couple of domains not in ISPCONFIG but exists on the system, such as lists.kalfaoglu.net. It helped me in that regard, and besides, I was not aware that the even though I don't have amavisd installed, the DKIM files would still be used by rspamd..
If these non-ISPC managed domains reside on the same server as your other ISPC managed domains then why not just manage those with ISPC too instead of creating a complicated workaround? Which also very well could have caused issues with system default functions. By that a mean conflicting with rspamd.
I can see the use if you need a mail server that can only send mails out and not recieve mails. Like if you have all your mail for one domain hosted with Microsoft and you need to send mails out through your website (microsoft closing down smtp access atm) but you don't want to add it to ispconfig mail server. If you do that, postfix will just send mails locally if a domain is registered and that could create some issues... We are in that situation ourselves and have a speciffic mail server set up for just smtp for microsoft customers.
Sure there are several use-cases for the tool, for example your situation. But that's not an ISPC system, which has dkim build-in.
