Our email server is setup for Domain POP/ Mail Bagging with our ISP for receiving only. Our MX Record resolves to our ISP mail host address. We have 2 IP addresses (redundancy purpose), 1 from our mail hosting ISP(ISP1) and the other from a different ISP.
Domain Name: abc.com.au
MX record points to: mailgate.ISP1.com.au
Question is can i setup PTR record for both IP addresses pointing to our domain (abc.com.au)?