I'm using the mailgun service and it asks me to setup mxa.mailgun.org and mxb.mailgun.org on my domain, which is fine but I want to use something different on a secondary domain to mask that it's using mailgun.
Is this scenario possible?:
maindomain.com has the following:
CNAME - mx1.maindomain.com - mxa.mailgun.org
CNAME - mx2.maindomain.com - mxb.mailgun.org
secondarydomain.com has the following:
MX - mx1.maindomain.com
MX - mx2.maindomain.com