On 12/5/25 11:23, BetaRays wrote: > Hello, > > I would like to run OpenSMTPD for two domains, each of which can send and > receive messages. > Right now, I have it set up for one domain, and use a configuration similar > to https://openports.pl/path/mail/opensmtpd-filters/dkimsign for DKIM. > > From my understanding of the DMARC standard, the DKIM signing domain should > match the domain using in From addresses. > I see how to extend this configuration to sign for all domains at once, but > how would I sign with only the domain that was used in the From address? > > Thanks for your help. > from the manpage: -d domain The domain where the public key can be found. This option can be specified multiple times to select the best domain during signing. If specified multiple times it looks at the domain component of the first mailbox in the from- header and tries to find a match. If no exact match can be found it looks for the closest parent domain. If no matches can be the first domain specified will be used.
So it already does what you want it to do and only signs for a single domain. martijn@
