DNS and NAT don't seem to like each other

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Guest

I feel dumb as a brick that I can't figure this out! Here's my situation:

For years my company used an ISP that gave us a range of real IP addresses.
I set up DNS and DHCP on my Win2k Server without any trouble and it worked
perfectly. Recently we were solicited by a new ISP that promised faster
service at a better rate. Needless to say that we switched. The good news is
the service is indeed faster. The bad news is I CANNOT get DNS to work.

Setup:
Firewall/Router (FW/R) statically configured with the one Class A IP address
assigned to us by the new ISP. DHCP is not enabled on the FW/R however NAT is
enabled.

The FW/R is connected to the hub as are both of my servers.

The primary server is Win2K (SP4). DHCP is configured to use IP adresses in
the 192.168.1.X range. The FW/R is specified in the DHCP scope. DHCP is
working great. All clients are assigned an IP address and can access the web
with no trouble. Incidentally I am running AD.

The domain name we use is DomainName.CompanyName.com. I have two name
servers provided to me by the web host. I also have two DNS servers provided
by the ISP. I have tried setting up DNS using the name servers from our web
provider and the DNS servers provided by the ISP. Nothing works. I know there
is a definate problem as logins take 2 minutes now (literally) whereas they
used to be 10 to 15 seconds. Also I cannot add a network printer to any
client by browsing the domain. I cannot change permissions on shares because
when I try to add someone I receive an error that says "The program cannot
open the required dialog box because no locations can be found."

This is driving me up a wall. Can anyone shed some light on this for me?
 
RBell said:
I feel dumb as a brick that I can't figure this out! Here's my
situation:

For years my company used an ISP that gave us a range of real IP
addresses. I set up DNS and DHCP on my Win2k Server without any
trouble and it worked perfectly. Recently we were solicited by a new
ISP that promised faster service at a better rate. Needless to say
that we switched. The good news is the service is indeed faster. The
bad news is I CANNOT get DNS to work.

Setup:
Firewall/Router (FW/R) statically configured with the one Class A IP
address assigned to us by the new ISP. DHCP is not enabled on the
FW/R however NAT is enabled.

The FW/R is connected to the hub as are both of my servers.

The primary server is Win2K (SP4). DHCP is configured to use IP
adresses in the 192.168.1.X range. The FW/R is specified in the DHCP
scope. DHCP is working great. All clients are assigned an IP address
and can access the web with no trouble. Incidentally I am running AD.

The domain name we use is DomainName.CompanyName.com. I have two name
servers provided to me by the web host. I also have two DNS servers
provided by the ISP. I have tried setting up DNS using the name
servers from our web provider and the DNS servers provided by the
ISP. Nothing works. I know there is a definate problem as logins take
2 minutes now (literally) whereas they used to be 10 to 15 seconds.
Also I cannot add a network printer to any client by browsing the
domain. I cannot change permissions on shares because when I try to
add someone I receive an error that says "The program cannot open the
required dialog box because no locations can be found."

This is driving me up a wall. Can anyone shed some light on this for
me?
Click to expand...

All clients and server must point to the local DNS server, which is usually
your DC. Using the DNS management console, select the properties of the DNS
server, on the forwarders tab put in your ISP's DNS. If the forwarders tab
is grayed out, delete the "." forward lookup zone.
If you are running NAT on the same server as DNS, make sure the DNS proxy is
not enabled (RRAS management console, NAT properties, Name resolution tab)
 
I tried your suggestion but I did not notice any difference even after
restarting RRAS and DNS services. I noticed that RRAS was not enabled
intially so I enabled it. My dilema persists.
 
I had posted this same message in the Windows Server section as well. Someone
answered my plea for help and it did the trick. I posted the response below
so others would have it if they encountered the same situation.

DNS 101:
All AD machines (DCs, member servers and clients) MUST always and ONLY use
the internal DNS server(s) that AD is using in their IP properties. If using
DHCP for your clients, make sure Option 006 ONLY lists the internal DNS
server(s) that AD is using.

For Internet resolution, DNS will use the root hints. If you want efficient
resolution, you can use a Forwarder to your ISP's DNS server. That is set in
DNS properties, Forwarders Tab.

If that rule has been followed, and you are still experiencing problems,
please post: an ipconfig /all from your DC and one of your clients.

Thanks!
 
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