Cannot Share internet thru dual NICs

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Guest

I have a Windows2K SP4 server with 2 nics. I have designated the NICS as
INSIDE (192.168.254.1)
and
OUTSIDE (10.0.1.1) (to broadband router)
This server is running DHCP, DNS, AD, RRAS, and IAS. The server is correctly
allowing clients to join its domain. It is correctly handing out IP Addresses
thru DHCP. DNS is working correctly ( as I can see from the fact that it is
getting DNS from itself and can resolve LAN names, and surf the internet
perfectly)

I have set up Routing and Remote Access and configured NAT. The two
problems I have are 1) Clients are not picking up a default gateway through
DHCP .. and
2) I cannot access the internet from a client through the server.

I have tried setting up the client on a static IP and setting the default
gaterway manually, but this does not result in an internet connection at the
client. The server internet connection on the OUTSIDE nic is working great.
 
The default gateway problem can be fixed by modifying the DHCP scope.
This should be giving the clients the internal IP of the server (ie
192.168.254.1) as the default gateway. After you change it, you may need to
do an ipconfig /release and ipconfig /renew on the clients to get the new
setting.

The second problem is DNS. The clients should be using this same address
for DNS (so that AD works properly). To resolve external addresses, you need
to modify your DNS server to forward requests it cannot resolve itself to a
public DNS service.

The default gateway setting on the LAN NIC should be blank. eg

Internet
|
router
|
10.0.1.1 dg router IP
RRAS
192.168.254.1 dg blank
|
clients
192.168.254.x dg 192.168.254.1

You will also need to add a route to your Internet router. It does not
have an interface in the 192.168.254 subnet, so it does not know where that
subnet is. You need to route traffic for 192.168.254 to the RRAS/NAT router.
eg

192.168.254.0 255.255.255.0 10.0.1.1

Otherwise this traffic uses the router's default route (which is back
out to the Internet!)
 
Bill ..
Question about this paragraph...
<quote>
"You will also need to add a route to your Internet router. It does not
have an interface in the 192.168.254 subnet, so it does not know where that
subnet is. You need to route traffic for 192.168.254 to the RRAS/NAT router.
eg
192.168.254.0 255.255.255.0 10.0.1.1
<end quote>

Do you mean add a route to the broadband router, or the Windows 2000 Router?
I am confused, since the broadband router cannot see the 192.168 subnet at
all.. It only sees the 10.0.1.x subnet held by the outside NIC. I am willing
to try this of course, I just wanted to be sure I understood you correctly.
Thanks for your excellent reply.
 
That is correct. The broadband router cannot see the 192.168.254
network. You need to add the extra routing to this router so that it
forwards traffic for 192.168.254 to the RRAS router, which can deliver it.
 
Bill...
thanks for your replies. I finally figured out what my problem was. It was
actually unrelated to RRAS. It turned outto be a simple DNS problem. After 2
hours of messing with it, i decided to try entering an external DNS IP and it
worked perfectly. Then I had to figure out why it was failing to work with
the local DNS server. I found an extra fwd lookup zone in DNS that had wrong
IP records in it. Deleting it fixed everything.
 
Glad to hear its OK.

Scott said:
Bill...
thanks for your replies. I finally figured out what my problem was.
It was actually unrelated to RRAS. It turned outto be a simple DNS
problem. After 2 hours of messing with it, i decided to try entering
an external DNS IP and it worked perfectly. Then I had to figure out
why it was failing to work with the local DNS server. I found an
extra fwd lookup zone in DNS that had wrong IP records in it.
Deleting it fixed everything.
 
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