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jackbensonFlag for United Kingdom of Great Britain and Northern Ireland

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static routes for Nic connected to ADSL modem


i want to know if i have configured my server nic's in the best way.

i have 3 servers.

each server has 2 nics
- 1 nic connects to the internal switch
- 1 nic connects to the ADSL modem so i can remote access the servers externally and for other services like inbound SMTP and HTTP

my domain IP4 settings are as follows:

nic connected to the internal switch
IP Address:
default gateway:

nic connected to the ADSL modem
IP address:
default gateway (blank as windows does not like have 2 default connectign to different networks)

[Please note that the server that has routing and remote access installed, that provides internet access to the network has the default gateway configured on the nic connected ADSL modem and the nic on the internal switch has no defautl gateway - and static routes are configured]

i then create the following static route so that inbound connections connected via the ADSL work:

route -p add mask metric 1

is this the right thing to do?


Avatar of jakethecatuk
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Close...but no cigar.

Your NIC that is connected to the ADSL modem needs to have the default gatewey set whcih will be the ADSL modem itself.

Your NIC for your internal network will not need a gateway address.  The reason for this is that the server will know that any traffic for has to go out of the internal NIC.  You should not need any static routes for your internal network unless you have more than one internal subnet.
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thanks - and i will not have a problem accessing the server from other servers/clients within the network?
nope - all devices within the subnet will have full communication with the three servers you are planning on changing.

If you do a 'route print' from a command prompt, you will see a line that covers your subnet with the gateway being your 192.168.16.x IP address
last question - on the nic that connects to the ADSL Modem - should the DNS server be the ADSL Modem IP or the DNS server on my domain?
You don't need a DNS server there.  All DNS queries will be handled by your internal NIC and internal servers.
sorry - i have removed the DNS server IP on the ADSL nic on a server that has a DNS server on. i get the following warning on that server when i try to close the TCP/IP Properties page:

"The DNS server list is empty. The local IP address will be configures as the primary DNS server address because Microsoft DNS server in installed on this machine"

I have 3 DNS servers on my network. i think i should leave these as the DNS servers for the ADSL nics only on servers that have DNS servers on? didn't say that the server had DNS installed on it.

You will need to ensure that the DNS address is the same as the IP address for that card.  Don't use as it may cause problems.
i should have said - but i didnt think....

so the DNS server for the ADSL nic should be if the IP address of the ADSL NIC is


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thank you - really appreciate your help!
very helpful!
i know this question is closed.. but i have just found an issue.

the the server that has exchange server on.. the exchagne best practive analyer is saying that all nic's on the server need to have atleast 1 DNS server.

i have taken all the DNS servers of the ADSL modem nic. what is the best thing to do in this case?


is exchange still working as it should do Jack?  If it is, don't stress too much about it.

TBH - your whole config is a bit unusual but as long as it works :)
exchange seems to be fine.

what would be a better way to configure servers to access from outside the network to multiple servers?