cryingvalor

Hey I need some clarification pls correct me if im wrong. Heres the situation:

I have a DSL connection at home, our ISP gave me 1 class C routable IP
address, 2 class C DNS address and configure it on my XP Box. So with this
kind of setup when i try to search for a website i am using our ISP's 2 DNS
address that they gave mo to resolve the website and using the default
gateway (the default gateway that i used is the .1 of the class C routable IP
address given to me by my ISP) to be able to connect to the internet, right?

But what is the difference if i configure my DSL configuration to a broadband
router (Linksys) and use it in a LAN with a win03 DNS server with AD, where
all XP Box is using the DNS server as their DNS.

crazijoe

Quite simple.
All computers on your LAN will be configured with your networks DNS server, even your DNS server will look at itself for DNS queries. In the DNS properties of your DNS server, you will have a fowarder configured with the IPs of your ISPs DNS servers.
When a workstation looks for a website (i.e. www.google.com), it will go to your DNS server. If your DNS server cannot resolve the query, it will foward it to your ISPs DNS server. Your ISPs DNS server says "Hey, the IP for www.google.com is 64.233.167.99." and relays that back to your DNS server which resolves the IP for your workstation.

cryingvalor

- ah ok but what if there is no forwarder what would happen?

crazijoe

Normally if no fowarder is configured, workstations on the LAN would be unable to resolve DNS names outside the LAN.

cryingvalor

Ok.....but if you if placed a default gateway configured with your DLS connection in your LAN but still not configuring forwarding on your DNs server. can workstations in the LAN resolve names outside the LAN.

Cellus

You would need to set up a forwarder if your network's DNS server can not resolve the name, as crazijoe said. Unless you are changing the DHCP/manual DNS settings on the workstations to ask your ISP's DNS instead of your local DNS, the workstations will be asking your local DNS. The local DNS has to be told to forward any name resolution it does not know to the ISP's DNS to be able to resolve outside the network.

This is SOP for networks. Setting up a forwarder is easy in Windows Server 2003, so you should not have any problems unless your routers/gateways are not permitting the DNS.

cryingvalor

Is it really necessary to implement forwarding. because in our network we have a linux box that shares internet in our LAN and is also our default gateway but our DNS servers are not configured to do forwarding. and so far we can access the internet.

also if i will implement forwarding on our DNS servers what should be my default gateway?

crazijoe

You probably have a little more network traffic on your LAN than what is really neccissary.

You must not confuse DNS and the default gateway. DNS only resolves names to IPs. A default gateway routes IP traffic.

If your linux box is configured as your router between your LAN and WAN, then it should be your Default Gateway.

If your workstations are configured with multiple DNS servers (i.e. your DNS server, ISPs DNS server, etc.), then it will query each server till it gets an answer. This is not an idea setup. All workstations on the LAN should have the LANs DNS server resolve all DNS names.

cryingvalor

Everything clear now... thank you