Re: DNS issues, reverse lookup, MX records

Yes, because you own the domain and the MX records reside in the *forward
lookup zone* for that domain - e.g. yourdomain.com. You decided to have
Yahoo host your DNS.

PTR records reside in reverse lookup zones, which are typically hosted by
"owner" of that block of IP addresses - which is your service provider AT&T
in this case.

This article on TechNet explains reverse lookups:
http://technet2.microsoft.com/WindowsServer/en/library/edf68cca-86f1-4b89-8e44-79f768963e951033.mspx?mfr=true
--
Bharat Suneja
MVP - Exchange
www.zenprise.com
NEW blog location:
www.exchangepedia.com/blog
----------------------------------------------



<bjriffel@xxxxxxxxxxx> wrote in message
news:1168016574.204996.147200@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
So even though our MX record is hosted at Yahoo, I can ask ATT to host
a PTR record for mail.ourdomain.com and point it to our static IP?


Bharat Suneja [MVP] wrote:
If they're the ones maintaining reverse lookup zone for your block of IP
address(es), yes.

--
Bharat Suneja
MVP - Exchange
www.zenprise.com
NEW blog location:
www.exchangepedia.com/blog
----------------------------------------------



<bjriffel@xxxxxxxxxxx> wrote in message
news:1168013166.746535.308430@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
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 issues, reverse lookup, MX records
    ... PTR records are added in reverse lookup zones by owner of that IP address ... Our website is hosted with Yahoo on a business account. ... IP on our T-1 for our new server. ... redirect Network Solutions DNS to them. ...
    (microsoft.public.exchange.admin)
  • Re: DNS issues, reverse lookup, MX records
    ... PTR records are added in reverse lookup zones by owner of that IP address ... Our website is hosted with Yahoo on a business account. ... IP on our T-1 for our new server. ... redirect Network Solutions DNS to them. ...
    (microsoft.public.exchange.admin)
  • Re: Usage Report show IP addr instead of computer names
    ... I didn't have Reverse Lookup configured for all of my subnets. ... The reverse DNS look-up is only query DNS server, ... Can you see the PTR record for the unresolved IP address, if not, please ... | the reverse lookups at 4:30, will that cause the Usage Report to identify ...
    (microsoft.public.windows.server.sbs)
  • Re: How to create a subdomain email address in Exchange 2003
    ... It's turn out to be some people keyin an invalid DNS ip address. ... I can send the mail out to other like gmail, yahoo mail. ... send mail from outside, it fail. ... send and receive is successful. ...
    (microsoft.public.exchange.admin)
  • 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)