Reverse DNS for Mail server

[mojo1979]

Hi,

I have just setup a new mail server and have just read i might need to create a reverse dns entry (PTR). Do I do this on my own domain, or is it something i need to request from my ISP?

Also would I use the public IP when creating it, or the internal IP?

Thanks!

Confused dns user

 

[FaiTHLeSS]

This PTR record will need to be created for the external(public) IP of your mail server, you will most likely have to request your ISP todo it for you.

You can use DNSSTUFF.COM to check if your external IP has a PTR record already. If it does and you want it changed to something else you will need to contact your ISP about this to.

 

[ShackDaddy]

You want to give the following information to your ISP:

1) The A-record for your mail server. Something like "mail.yourdomain.com". Make sure the record exists.

2) The external IP address that maps to "mail.yourdomain.com". They will create a PTR record from that that will looks something like this:

"45.95.67.43.in-addr.arpa PTR mail.yourdomain.com"

Where 43.67.95.45 is your mail server's public IP address.

ShackDaddy
Shackelford Consulting

 

[mojo1979]

Ok, probably what I didn't mention is that currently mail is hosted by yahoo. On the email management console they provide I can create A record, and then point the mx record to the public ip of my mail server.

Is this enough, or do I still have to get my ISP to create an A and PTR?

Yahoo is not my ISP.

Thanks

 

[ShackDaddy]

Clarify: is your mail server hosted by yahoo, or is it your own, in your own network? Will you be sending mail out through Yahoo, or from your server, or from your server through Yahoo? The answer to the PTR questions depends on this.

ShackDaddy
Shackelford Consulting

 

[mojo1979]

sorry, wasn't very clear. At the moment it is hosted by Yahoo. I have just installed my own exchange server onsite, so will use my own server to send and recieve email. To do this i have had to create an A record for my server on yahoo's email console (as advised by yahoo support).

 

[ShackDaddy]

Ok. You will also have to have your ISP create a PTR record that points at the A record that you created. And you'll also be pointing an MX record at your A record.

ShackDaddy
Shackelford Consulting