Jason Long wrote:
Thank you. Can you tell me how can I setup my Postfix server with A record
You just add an A record with a suitable name for your server. There's nothing Postfix-specific about this.
Or how can I change the DNS server two support two MX records?
I'm not aware of any DNS server software that limits the number of MX records.
I *have* met all too many DNS management tools that make bad assumptions about things like this.
You should talk to your IT support and/or hosting provider, because both of these are specific to however your DNS records are managed, and neither has anything to do with Postfix configuration.
-kgd