Subdomain Delegation to at&t

Here’s what’s going on -

We switched to at&t for an ISP. We have a managed T1 through them. We have all of our web hosting and DNS hosting for our domains (there are 7 or 8 of them) going through Dreamhost. We want to keep it that way. Custom MX records are setup through Dreamhost to resolve to our at&t IP address, where our Exchange server is. Incoming and outgoing mail work fine.

The problem is with reverse DNS. I searched on this forum, as well as on Experts Exchange, and the consensus is that the person who owns the IP address is responsible for rDNS. Because rDNS isn’t working (at&t owns our address), people at places like and aren’t getting our emails because those companies use rDNS lookups to block spam.

I contact at&t about adding a PTR record in their DNS to reverse-resolve our at&t IP address to They basically said that they can, but they won’t without having our DNS hosting through them.

We pulled 3 at&t reps in the office today and my boss (the COO) went nuts on them, and asked them why our previous internet provider was more than willing to set up a PTR record for us, but at&t wasn’t. at&t specified that it wasn’t “best practices” under some RFC, and gave us options.

Basically at&t said that our option is to move our DNS over to them, delegate an IP to Dreamhost so that they could add the rDNS record, or be SOL. I searched and Dreamhost won’t do the delegated IP w/ rDNS (which I can understand) so basically our only option is to move DNS to at&t. After fighting with the guy I finally got him to admit that if we moved only the subdomain over to at&t that that would be sufficient for at&t to fix our problem.

I’ve been searching for days but can’t find where on’s web panel it’ll let me do this. Do I just find out the IP address that at&t wasn’t me to use and set up a DNS A record and point them subdomain to them? Or is there another special process?

This has been driving me crazy and I’ve got 500 people breathing down my back… someone please help. :frowning: