I am seeking to make emails my server sends have a higher reputation by implementing DKIM and DMARC. I already am passing SPF with the proper DNS entries.
I also have a working Postfix/Dovecot installation with TLS turned on, but the certificates are just to the snakeoil.crt/.pem
files found in /usr/ssl
that came with my server setup.
My question is about the certificate I want to use. I only have experience setting up a signed digital certificate for a domain name for a website. Can I get another signed certificate and use it BOTH for Postfix/Dovecot TLS as well as the DKIM key? Is it possible to use the same signed certificate for my website, Postfix/Dovecot and DKIM? Thank you for your assistance!