CentOS

Why do this?

When you have an email server, it can be a good idea to add DMARC checking to the server, so you will accept less forged email.

Why install DKIM?

While I was looking at setting up DMARC, I noticed most emails I sent, we marked with a DMARC fail, because of unalignment. This is because of the difference between the Mail From and the Header From were in different domains. To be able to probably fix this, I wanted to see if DKIM could help.