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PTR Records not taking effect after changing IP addresses

Hey folks,

I have a problem. I just installed a new T1 circuit here in the building which put us on a new LAN Block with AT&T. Since the IP address of our Exchange Server changed. I had our DNS provider add a PTR record pointing to our server for our MX record. However, it's been a week and still no reverse DNS changes show up. AOL and certain other domains can't receive e-mail from me until I fix this. AT&T won't take care of the PTR record unless they are our primary DNS provider. So, I had our primary DNS provider take care of it. Any thoughts?
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Your DNS provider isn't responsible for your PTR records, your ISP is.  You will need to talk to AT&T.

If they won't do it (as you indicate) hang up, and call again - there should be zero reason for them to not do this.

That said, I have a recent (horrible) memory of another user here with a very similar problem - the only solutions were to get AT&T to do the lot, or to change ISPs...
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So, AT&T will have to be our Primary DNS provider? That's a nightmare to switch DNS, no?
Not really - get them to setup the same hosts as you have now, then redirect your domain

If you bitch and complain to them loud enough (and you have every right to) you should be able to demand that someone senior looks at it.

In times where I have switched DNS hosts, there has been zero downtime, and it took very little effort - anyone at the ISP that knows how the internet works should be able to sort it for you quickly.
So I need to bitch really bad at AT&T or get them to be our primary DNS provider....which do you think is easier?
both :)

they wont do what they should, which is just give you a ptr - but if you bitch loud, they might be your primary dns provider without stuffing it up...
My DNS provider has added PTR records that point to my IP though...why won't that work?
Because your DNS provider is not responsible for that block of IP addresses - I am surprised they even agreed to do it actually, you must have got a hold of someone "new" :)

Think of it the other way, if I configure my DNS server to host your PTR record, what would stop me from setting it incorrectly (as some kind of DoS attack)?

What stops me is that only the server responsible for that block of IPs is listened to - and the server responsible is AT&T
Gotcha...their DNS department isn't open till 7am...I'll start bitching at 7:01am...
Lol, remember, if you get stuck dealing with an idiot, hang up and call back :)

Happy hunting
Thanks. I will check it out and see what happens. I will post my results to finish off the question.
So, I talked to AT&T...they delegated control of the reverse DNS to my hosting company before we even installed the T1 Circuit. The guy at AT&T told me to call my host and make sure that they have not set up the PTR in Full C-Class because the reverse DNS will not point at our Lan Block in that case. In our case, my host must set up a PTR in Partial C-Class to make sure that our lan block is shown. Make sense? I don't know a whole lot about DNS...

How many IP addresses do you have from AT&T?
.224 thru .239
See, for only 16 address, I would not expect them to delegate reverse DNS hosting.  If we were talking a whole C class, then maybe.

Talk to your DNS host and ensure they have done it right.

I am looking around for a site that will test to see who is responsible for the ip addresses (like a whois for domain names) without much luck...
I just heard back from our DNS provider. I had them add our PTR as a partial C-Class and they replied telling me that they have accomplished what I requested...we'll see what happens. How long you think it should take? Not long, right?
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Well, this is the message I got from them...check out what I had them do and tell me if that's right.

Dear Mike,

Thank you for contacting Verio Technical Support regarding PTR Records.   Your case number is xxxxxx.  Please reply to this e-mail, keeping the subject line the same for additional correspondence on this issue.

I have added the PTR records in the manner that you specified as shown from your message below.  Please let us know if we can assist you further.


Jon F.
Technical Support
MPS/VPS Systems

==== Excerpt from your message received 3/7/2008  8:46:08 MST ====
>I do have a problem. AT&T, our ISP has delegated Reverse DNS control to
> and However, they show that you submitted
>the PTR records as a Full C-Class instead of a Partial C-Class. We need
>to make sure that Verio has set up the PTR Records as a PARTIAL C-Class
>record to point to our domain. Right now, AT&T is showing that you've
>set it up as FULL C-Class record. We own a LAN Block of
>We need the following-->
>1. to point to
>2. to point to
>Please call me with any questions or concerns.
We just ended up switching our DNS to AT&T...easier. Our host told us to do that because they were unable to help us with reverse DNS. Thanks for all your help, though!
As a follow up, the entire solution was to have AT&T host our DNS and just swap from our current DNS provider. No big deal. E-mailed AT&T our Zone File records, they propagated things to their servers, I pointed to their servers, and things were working within 20 minutes. Thanks for all the help!!