Hi Gureey,

The forward - reverse DNS match can be done with your ISP's domain, or with
your domain. Either way will work. Remember that although it is possible
to have the same IP address associated with many A records, only one PTR
record will display for an IP address. What your ISP is doing is allowing
you to use that one PTR record to show your domain instead of theirs.

What this does (among other things) is that when someone does a traceroute
to your network, they will see your domain instead of the domain of your
ISP. Also, there is a choice of only setting up reverse DNS on the IP
address of your mail server, or setting it up for all your IP addresses. It
is generally a good idea to set it up for all IP addresses, but as Herb
said, it isn't absolutely necessary.

--
Greg Lindsay [MSFT]

Disclaimer: This posting is provided "AS IS" with no warranties, and confers
no rights.

"Herb Martin" <news@learnquick.com> wrote in message
news:OjIb1l2LHHA.4000@TK2MSFTNGP06.phx.gbl...
>
> "Gureey" <Gureey@discussions.microsoft.com> wrote in message
> news:0BEF2DC2-2231-4893-B703-488673566AE8@microsoft.com...
>> Thanks Grey and Herb,
>>
>> I understand you point. But with our previous ISP, i didnt made any entry
> in
>> our DNS. My previous ISP only create a record in their domain as you
>> describe, pointing toward our IP address .
>
> You don't actually HAVE to do that -- but generally it is a good
> idea.
>
> Some (many/most) receiving SMTP servers will test for that PTR
> record, some (not as many) will test for a match back to an A
> record in your PUBLIC DNS. Most which do this expect the
> name to match the HELO name of the SMTP server no matter
> WHAT you call your SMTP server internally or for which
> zones/domains it sends email.
>
>
>> Any ways thanks for you response..
>>
>> "Greg Lindsay [MSFT]" wrote:
>>
>> > I agree with Herb, this is an ISP that is taking the trouble to give
>> > you
>> > more than just generic reverse DNS entries in a domain that they own.
>> > That's kind of rare.
>> >
>> > The extra entries they are sending to you is just so you can complete
> the
>> > loop (PTR = A record = IP address). If they were using one of their
> domains
>> > for the reverse entries, they would add these themself, but since they
> are
>> > using your domain, they are giving you the information. The "loop" I
>> > mentioned is required by some email servers. If you don't have
>> > matching
>> > forward and reverse DNS, they will reject your emails.
>> >
>> > --
>> > Greg Lindsay [MSFT]
>> >
>> > Disclaimer: This posting is provided "AS IS" with no warranties, and
> confers
>> > no rights.
>> >
>> > "Herb Martin" <news@learnquick.com> wrote in message
>> > news:OzSaZ3tLHHA.5000@TK2MSFTNGP03.phx.gbl...
>> > >
>> > > "Gureey" <Gureey@discussions.microsoft.com> wrote in message
>> > > news:C18A8BEB-FB8A-43D8-9FBA-3337DE8840DE@microsoft.com...
>> > >> Hello Friends,
>> > >>
>> > >> I asked my ISP to setup a reverse DNS for our IP address. I get a
>> > >> response
>> > >> to setup a fwd in my zone file and then my ISP add reverse. He also
> send
>> > > me a
>> > >> list of name with corresponding IP address to add in my forwad zone
> like
>> > >>
>> > >> gw IN A 198.168.0.49
>> > >> hostXX IN A 123.34.345.22
>> > >>
>> > >> then they add following in their reverse zone.
>> > >>
>> > >> 49 IN PTR gw.xxxxxxx.com
>> > >> hostxx IN PTR hostxx.xxxxx.com
>> > >>
>> > >> Is this is the way to created REV DNS.
>> > >
>> > > Yes (it sounds like) the ISP is being kind (not all are) and
>> > > allowing YOU to pick the names -- many ISPs just give you
>> > > a generic record name in the PTR and you have to figure out
>> > > how to deal with it to make it convenient (CNAME etc.).
>> > >
>> > >> I think they only have to create PRT
>> > >> record in their DNS reverse zone pointing towards our IP.
>> > >
>> > > Correct but that is what you said above:
>> > > > then they add following in their reverse zone.
>> > > > 49 IN PTR gw.xxxxxxx.com
>> > > > hostxx IN PTR hostxx.xxxxx.com
>> > >
>> > >> Please tell how can I setup this, Coz we are facing problems to
> sending
>> > > mail
>> > >> from our server.
>> > >
>> > > You will also need to give your EMAIL server the same
>> > > "HELO" or SMTP Server name in the Email configuration.
>> > > This is specific to the particular SMTP server software and
>> > > the name for this setting may vary but it is the "official" name
>> > > of the SMTP server when it SENDS email, i.e., the one it
>> > > reports when it says "HELO" to other SMTP servers.
>> > >
>> > >> Any is appreciated
>> > >> Regards
>> > >> G.
>> > >
>> > >
>> >
>> >
>> >
>
>