NSLookup Shows Local Machine Name

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Hello Everyone and thanks for your help in advance. I am setting up new DNS
and mail servers and am relatively new to DNS. My problem is, I have set up
mydomain.com. It is hosted on a machine mydomain.local. There is also a mai
server, mail.mydomain.com that is hosted on mail.mydomain.local. My problem
is, in the headers of emails, it shows the mail as received from
mail.mydomain.,local. Also, in doing a DNS lookup through DNSReports, it
shows the primary nameserver as machinename.mydomain.local. I am getting
correct resolution on the domains, but I am concerened about disclosing the
machine names. There does not appear to be any reference to the local
machines in this particualr zone. So I am not sure why this is happening.
Any insight on this issue would be greatly appreciated. Thanks.
 
kmcnet said:
Hello Everyone and thanks for your help in advance. I am setting up new DNS
and mail servers and am relatively new to DNS. My problem is, I have set up
mydomain.com. It is hosted on a machine mydomain.local. There is also a mai
server, mail.mydomain.com that is hosted on mail.mydomain.local. My problem
is, in the headers of emails, it shows the mail as received from
mail.mydomain.,local.
Click to expand...

Normally the email server will report whatever Machine name
is ''official" for the computer OR whatever you specify in your
SMTP server software -- my guess is you specified the .local
name or let it default.

Once cannot fully answer this question without knowing the
software you are using.
Also, in doing a DNS lookup through DNSReports, it
shows the primary nameserver as machinename.mydomain.local.
Click to expand...

I doubt that it is actually working (publicly like that with
DNSreports) using .local.

This is one of those cases where you should likely use the
actual names or risk confusing anyone trying to help you.
I am getting
correct resolution on the domains, but I am concerened about disclosing the
machine names. There does not appear to be any reference to the local
machines in this particualr zone. So I am not sure why this is happening.
Any insight on this issue would be greatly appreciated. Thanks.
Click to expand...

If you have a public email server there can be little harm in
giving us the actual names and precisely what you have and
wish to have, along with your software and versions.
 
kmcnet said:
Hello Everyone and thanks for your help in advance. I am setting up
new DNS and mail servers and am relatively new to DNS. My problem
is, I have set up mydomain.com. It is hosted on a machine
mydomain.local. There is also a mai server, mail.mydomain.com that
is hosted on mail.mydomain.local. My problem is, in the headers of
emails, it shows the mail as received from mail.mydomain.,local.
Click to expand...

The headers will *include* the server's full name (mail.mydomain.local), as
will a telnet to port 25 on your public IP or A record specified in your MX
record. This is normal -
Also, in doing a DNS lookup through DNSReports, it shows the primary
nameserver as machinename.mydomain.local.
Click to expand...

Unusual...are you 100% sure? .local isn't a top level domain and can't be
used on the Internet. Are you looking up mydomain.com ? That's what you
should be looking up - if you see .local referenced in there anywhere but in
your server's mail greeting banner on the mail test, your public DNS isn't
set up right.
I am getting correct
resolution on the domains, but I am concerened about disclosing the
machine names.
Click to expand...

Why? Anyone who can send you mail can see your mail server's name. It
doesn't represent a security risk. I don't know what your mail system is,
but security does not begin there - it begins with protecting your network
at the perimeter to block unwanted/dangerous inbound traffic, keeping your
servers patched, using a good security/password policy, etc etc etc....
 
In
kmcnet said:
Hello Everyone and thanks for your help in advance. I am
setting up new DNS and mail servers and am relatively new
to DNS. My problem is, I have set up mydomain.com. It
is hosted on a machine mydomain.local. There is also a
mai server, mail.mydomain.com that is hosted on
mail.mydomain.local. My problem is, in the headers of
emails, it shows the mail as received from
mail.mydomain.,local. Also, in doing a DNS lookup
through DNSReports, it shows the primary nameserver as
machinename.mydomain.local. I am getting correct
resolution on the domains, but I am concerened about
disclosing the machine names. There does not appear to
be any reference to the local machines in this particualr
zone. So I am not sure why this is happening. Any
insight on this issue would be greatly appreciated.
Thanks.
Click to expand...

Is you zone Active Directory integrated?
You will have to change it to standard primary, the change the Primary Name
Server on the SOA record to reflect the name of your NS records listed at
the gTLD servers for your domain.
Note- If this zone is the zone for an AD domain the primary name server will
change back to the DC name once it is refreshed from AD.
 
In
kmcnet said:
Hello Everyone and thanks for your help in advance. I am setting up
new DNS and mail servers and am relatively new to DNS. My problem
is, I have set up mydomain.com. It is hosted on a machine
mydomain.local. There is also a mai server, mail.mydomain.com that
is hosted on mail.mydomain.local. My problem is, in the headers of
emails, it shows the mail as received from mail.mydomain.,local.
Also, in doing a DNS lookup through DNSReports, it shows the primary
nameserver as machinename.mydomain.local. I am getting correct
resolution on the domains, but I am concerened about disclosing the
machine names. There does not appear to be any reference to the
local machines in this particualr zone. So I am not sure why this is
happening. Any insight on this issue would be greatly appreciated.
Thanks.
Click to expand...

IN addition to everyone's responses, I would suggest to use a separate DNS
server to host your external data. It *appears* that you are using an
internal DNS hosting your AD info. If you can confirm that, please let us
know.

Maybe you can help us to help you better by providing the actual name. As
Lanwench said, it's really not a security issue to post the name, unless you
feel you haven't secured your mail server properly or you have relaying
allowed?

--
Regards,
Ace

Please direct all replies ONLY to the Microsoft public newsgroups
so all can benefit.

This posting is provided "AS-IS" with no warranties or guarantees
and confers no rights.

Ace Fekay, MCSE 2003 & 2000, MCSA 2003 & 2000, MCSE+I, MCT, MVP
Microsoft Windows MVP - Windows Server - Directory Services

Security Is Like An Onion, It Has Layers
HAM AND EGGS: A day's work for a chicken;
A lifetime commitment for a pig.
 
Hello Everyone and thanks for your response. I am using Exchange 2003 on one
Windows 2003 box. The DNS is being handled by another 2003 box within the
network, that is integrated with Active Directory. The domain name is
pocanticolane.com. My primary question is, will I have any security or
routing issues because of this?

Again, everyone's help is greatly appreciated.
 
kmcnet said:
Hello Everyone and thanks for your response. I am using Exchange
2003 on one Windows 2003 box. The DNS is being handled by another
2003 box within the network, that is integrated with Active
Directory. The domain name is pocanticolane.com. My primary
question is, will I have any security or routing issues because of
this?

Again, everyone's help is greatly appreciated.
Click to expand...

If you're hosting your public DNS in-house, it needs to be on another
server, ideally in your DMZ or something. Not an AD-integrated DNS server.
Do not mix your AD DNS with your public DNS.

I generally advise against this for small offices - keep your DNS hosted
externally, at your ISP, registrar, whatnot. It's a lot to handle/manage &
you're unlikely to have the kind of redundancy built in that your ISP etc.
would.
 
Again, thanks for the help. I think you have assisted me in the past, and as
I had mentioned, this is a test lab for my learningn purposes. Could someone
clue me in as to the ramifications of integrating the domain with AD or not?
 
kmcnet said:
Again, thanks for the help. I think you have assisted me in the
past, and as I had mentioned, this is a test lab for my learningn
purposes. Could someone clue me in as to the ramifications of
integrating the domain with AD or not?
Click to expand...

Integrating your public DNS with your AD DNS? I don't have any links for
you, sorry. It is just a Very Bad Idea and will Cause Major Problems. Don't
do it. :-)
 
In
kmcnet said:
Again, thanks for the help. I think you have assisted me in the
past, and as I had mentioned, this is a test lab for my learningn
purposes. Could someone clue me in as to the ramifications of
integrating the domain with AD or not?
Click to expand...

This is NOT recommended.

Reasons NOT to host a hostname server (DNS server) for public resolution of
your external domain name on your AD domain controller's DNS server:

1. Exposing your internal data to the world (why would you want to do
that?).
2. Exposing your DC to the world (why would you want to do that?).
2. Mixing private and public IPs on the same server is very PROBLEMATIC, to
put it lightly.
3. The private IP of the SOA on the internal DNS for public use will cause
issues.

As Lanwench said, you'll need TWO SEPARATE DNS servers that are not part of
your internal AD domain (a standalone), with most services disabled other
than what's required (no IIS, no messenger service, no NetBIOS, uninstall .
Hosting a nameserver for external public use requires two nameservers for
each domain, as per the registrar rules.

Believe me, using your registrar's hostname servers is way easier. Less
headaches, less hardware, and sleeping better at night not having to worry
about anyone trying to exploit any vulnerabilities on your machine.


Ace
 
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