I'm having problems with my mail server and Reverse DNS. Some mail servers are not letting me connect and I think this is due to reverse DNS not being setup correctly.
I have a set of IP addresses, xxx.xxx.xxx.199 points to the gateway and xxx.xxx.xxx.198 points to the mail server. Our A record of mail.DOMAIN.COM.AU (which has IP xxx.xxx.xxx.198) is used as the MX record.
When the mail server connects to another mail server I can see that it shows up as the gateway's IP of xxx.xxx.xxx.199. I have setup the PTR reverse DNS record to be mail.DOMAIN.COM.AU on both IP addresses of xxx.xxx.xxx.199 and xxx.xxx.xxx.198.
I'm still not allowed to connect to mail servers that check reverse DNS though.
Thanks for your help.