Configuring private name servers and reverse DNS

I have a VPS setup to host five domains from a single IP address. After some help from a previous post here, my DNS for the main domain has this configuration:

; cPanel first:11.34.2.8 (update_time):1458686884 Cpanel::ZoneFile::VERSION:1.3 hostname:supernova.lamardesigngroup.com latest:11.54.0.20
; Zone file for lamardesigngroup.com
$TTL 14400

lamardesigngroup.com.   86400   IN      SOA     ns1.lamardesigngroup.com.       rlamar4088.aol.com.     (
                                            2016032103 ;Serial Number
                                            86400 ;refresh
                                            7200 ;retry
                                            3600000 ;expire
                                            86400 ;minimum
    )
lamardesigngroup.com.   86400   IN      NS      ns1.lamardesigngroup.com.
lamardesigngroup.com.   86400   IN      NS      ns2.lamardesigngroup.com.
lamardesigngroup.com.   14400   IN      A       212.1.213.8

lamardesigngroup.com.   14400   IN      MX      50       lamardesigngroup.com.
mail    14400   IN      CNAME   lamardesigngroup.com.
www     14400   IN      CNAME   lamardesigngroup.com.
supernova       14400   IN      A       212.1.213.8
ns1     14400   IN      A       212.1.213.8
ns2     14400   IN      A       212.1.213.8

and here is how I setup my Reverse DNS zone:

; cPanel first:11.54.0.21 (update_time):1459092416 Cpanel::ZoneFile::VERSION:1.3 hostname:supernova.lamardesigngroup.com latest:11.54.0.21
; Zone file for 213.1.212.in-addr.arpa
$TTL 14400
213.1.212.in-addr.arpa. 86400   IN      SOA     ns1.lamardesigngroup.com.       bobl.lamardesigngroup.com.      (
                                            2016032407 ;Serial Number
                                            3600 ;refresh
                                            7200 ;retry
                                            1209600 ;expire
                                            86400 ;minimum
    )

213.1.212.in-addr.arpa. 86400   IN      NS      ns1.lamardesigngroup.com.
213.1.212.in-addr.arpa. 86400   IN      NS      ns2.lamardesigngroup.com.
8       14400   IN      PTR     lamardesigngroup.com.

When running a DNS check on lamardesigngroup.com I get this error about my reverse DNS.

Reverse MX A records (PTR) ERROR: No reverse DNS (PTR) entries. The problem MX records are:
8.213.1.212.in-addr.arpa -> no reverse (PTR) detected

What changes do I need to make to get this setup properly? My hosting provider gives me a primary nameserver IP of 31.220.19.53, do I need to use that somewhere in here?

Answer

Normally, your IP address provider should configure the PTR record. Unless the PTR record has been delegated you won't be able to configure a PTR visible to external DNS checkers. If it is delegated, the address format will be different. You can check external DNS for your IP. It appears you do currently have a PTR record.

You need only one MX server for all the domains. The fully qualified domain name of the MX should be what is returned by the PTR record. I would suggest you use a name like smtp.lamardesigngroup.com. as your MX. It can have the same IP address as lamardesigngroup.com.

Using the same IP for ns1 and ns1 will eventually cause you issues. Do try to find someone to mirror your DNS. There are reliable free DNS mirrors.