Re: DNS issues, reverse lookup, MX records

We have a dedicated T1 from AT&T, so does that mean that we need to ask
AT&T to add a PTR record for server.ourdomain.com for our static
external address?


Bharat Suneja [MVP] wrote:
PTR record is a reverse lookup record that maps your IP address to the
fqdn - opposite of what an A record does.
PTR records are added in reverse lookup zones by owner of that IP address
block.
Typically for consumer DSL/cable connections, even though you may get a few
static IP addresses, the service provider will maintain the reverse lookup
zone. Talk to your service provider.

If you have a block of IP addresses and want to maintain your own reverse
lookup zone (doubtful in this case since you've outsourced your forward
lookup zone), you can try talking to your service provider about delegating
reverse lookup for your block of IPs.
--
Bharat Suneja
MVP - Exchange
www.zenprise.com
NEW blog location:
www.exchangepedia.com/blog
----------------------------------------------



<bjriffel@xxxxxxxxxxx> wrote in message
news:1168010304.912925.304150@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hello,

I've done some searching in the groups, but I'd like to pose a specific
scenario. We are getting these errors:

#4.7.1 smtp;450 4.7.1 Client host rejected: cannot find your reverse
hostname,


This is the situation. Our domain name is registered with network
solutions. Our website is hosted with Yahoo on a business account.
Yahoo used to host our email as well. Recently we put in a local SBS
2003 server to host our Exchange locally. Originally our Network
solutions account had all DNS pointing to Yahoo's name servers, as it
should have. We wanted to switch the MX record to point to our static
IP on our T-1 for our new server. However, we can't have the www
address point to a single IP with Yahoo. Yahoo requires that we just
redirect Network Solutions DNS to them. So we reverted all DNS back to
Yahoo.

Now Yahoo has static entries for www and mail .domain.com pointing to
internal yahoo server, which we can't change. We added a record for
our mail server: server.domain.com and pointed it to our static
external IP address. We also created an MX record for
server.domain.com. Email started flowing in as expected.

However now some email systems, most notably AOL and Comcast, are
resolving our name it seems. We are getting the message I posted
above. Many of the postings I've read say that we need to add a PTR
record for our mail server. Is that on our local internal DNS or on an
external? If it is external DNS, then whos? Our ISP (AT&T) or on
Yahoo?

Thank you,
Brandon Riffel


.

Relevant Pages

  • Re: DNS gives UnKnown to nslookup Default Server results
    ... Okay, I'm sort-of blind, but learning quick, when it comes to DNS service ... Is it normal to have only this much under the Reverse Lookup Zones? ... >> Default Server: UnKnown ...
    (microsoft.public.windows.server.dns)
  • Re: DNS issues, reverse lookup, MX records
    ... Yahoo host your DNS. ... PTR records are added in reverse lookup zones by owner of that IP ... Our website is hosted with Yahoo on a business account. ...
    (microsoft.public.exchange.admin)
  • Re: Difference between DNS CName record and Domain Name Server?
    ... > provider is not yahoo. ... > to my web host provider's name server, ... > also can change the DNS CName or A record. ...
    (microsoft.public.win2000.dns)
  • Re: DNS issues, reverse lookup, MX records
    ... If they're the ones maintaining reverse lookup zone for your block of IP ... Our website is hosted with Yahoo on a business account. ... IP on our T-1 for our new server. ...
    (microsoft.public.exchange.admin)
  • Re: SMTP Problem
    ... > I am in the process of setting up a new exchange server 2003 and seem to ... > be having a problem sending mail to yahoo users at the moment. ... Not sure if it's a DNS problem, but you may try the following; ... isn't blocking TCP DNS queries, if it doesn't work, revise your ...
    (microsoft.public.win2000.dns)