DNS Problem

[William Oliveri]

Hi all,

We have a small W2K Active Directory network with the DNS Suffix as
mydomain.com where mydomain is exchanged for our domain name. This is fine
and all is working well. However, we have an off site mail server which is
not part of our AD domian and where the mail server address is
mail.mydomain.com. Whenever we set the DNS Server IP in DNS settings on the
client to our DNS Server they can get to the internet fine but cannot
retrieve their email and I believe it's because the suffixes are the same.


Is there anyway in DNS to tell the DNS Server that when a request comes in
for mail.mydomain.com to forward that request to the mail server?


Or Is there another way to solve this problem.

Thanks,

Bill

 

[Herb Martin]

We have a small W2K Active Directory network with the DNS Suffix as

mydomain.com where mydomain is exchanged for our domain name. This is

fine

Actually it's "exchanged for" mydomain.com <-- the AD domain name includes
the
whole dns zone/domain name.

and all is working well. However, we have an off site mail server which is
not part of our AD domian and where the mail server address is
mail.mydomain.com.

Perfectly normal -- add records BOTH in your External DNS and your
Internal DNS (each manually and separate) for this "mail" server address
and MX record.

Whenever we set the DNS Server IP in DNS settings on the
client to our DNS Server they can get to the internet fine but cannot
retrieve their email and I believe it's because the suffixes are the same.

Possibly but more likely because you haven't added the Mail server
(properly) to the Internal DNS servers.

BTW, your clients SHOULD/must be set to use those INTERNAL DNS
servers -- the internal servers forward to the Internet (ISP or recurse from
the
root themselves) for ZONE they cannot cover locally.

Is there anyway in DNS to tell the DNS Server that when a request comes in
for mail.mydomain.com to forward that request to the mail server?

Not really. Forwarding is done on an all or nothing basis. If the server
is authoritative
(covers) a zone then it will not forward for records IN THAT ZONE.

But you don't need that. Just add the records in both places.

 

[Herb Martin]

Thanks Herb,

I do not understand External DNS and Internal DNS. I from my AD Dns

External == available to Internet users (your customer, friends, etc.)

Internal == avaible ONLY ot your INTERNAL (corporate/domain) users.

Server I can ping the mail server by name and on all my clients I have them
pointing to my AD Dns Server but from the clients I cannot ping the mail
server. I added an MX Record in the AD Dns server but that still did not
help.

You need a HOST and an MX record usually. Add these both. The A record
(or host record) is for the Name->Address mapping and the MX record is
for the Domain/Zone/Company name to EMAIL server name mapping.

 

[Kevin D. Goodknecht Sr. [MVP]]

In William Oliveri <[email protected]>
posted their concerrns,
Then Kevin D4Dad added his reply at the bottom.

I do not understand External DNS and Internal DNS. I from my AD Dns
Server I can ping the mail server by name and on all my clients I
have them pointing to my AD Dns Server but from the clients I cannot
ping the mail server. I added an MX Record in the AD Dns server but
that still did not help.

Any other suggestions?

You don't need an MX record internally, MX records are only for SMTP servers
to see so they know what SMTP server to send mail for the domain they are
in.

What you need is inyour Forward Lookup Zone for your internal Domain, create
a new host named "mail" pointing to the IP address of your mail server.