Help With RoutingTable

How do I clear the routing table on my Windows 2000 Pro machine
Connected to a nt4 Domain With an Nokia M1122 adsl router

We are in the process of changing to an cable modem internet
and soon as the router is taken out of the network my computer looses connection to the network and it is some to do with ip address that is causing it

I need urgent help

 

Have you configured the new router with the correct IP address for your network? Needs to be the same as the old router, for the other computers to use it as a "gateway ". Are you using DHCP?

 

There are DHCP or dns servers running on the network
The router we are taking out was acting as DHCP sever but it is not connected when I have this problem
The gateway is being pointed to the cable modem (which does not have any routing or dhcp services on it)
As part of getting this cable modem running we will have to get a router
because we are hosting web and e-mail

 

You can use "route delete" at the command prompt to clear out entries in your routing table, (try "route help" to get instructions on using the route command)

However, I would be very surprised if that is the source of your problem.

I can't work out how your systems are arranged from your description. The fact that you are using a cable modem and express a desire to get a router at a later date, suggests to me that the cable modem is connected to a PC. If that is a case you will need to:

1. Share the cable modem connection some way on the machine it is connected to. Your option range from packet forwarding, internet connection sharing to installing some sort of proxy.

2. Set the default gateway on the other PC to the INTERNAL IP address of the machine with the cable modem.

Also think about how you are going to firewall the system. That might be a theme for a new thread.

 

Kevinwnz - at the risk of telling you things you already know, here is a 'quick & dirty' (Americanism for short and over-simplified) explanation of routers and routing. If you are already very familiar with routers and routing tables, just ignore the rest of this.

The way TCP/IP operates, all PCs on the same 'network' can see and talk to each other. Network, in this case, meaning the same physical wiring and the same IP address range.

However, they can't work with devices on another network because they wouldn't know how to find them even if it were physically possible.

A Router, be it a seperate device or a PC with routing tables set up, is simply a device that knows how to find other networks. It listens on a network for any packets addressed to devices outside that network and when it spots one, traps it and tries to send it along toward the other network.

The way most folks with home networks or simple office networks think of them is as a sort of magical gateway to the internet and they are certainly that but only because they have route information stored that allows internet packets to be sent on to other internet devices.

If my office network was divided into IP address ranges A, B, C and we had internet connectivity, my router on A would need to have information about B, C, internet and be able to pass info along to them when a PC on A needed to talk to a device that wasn't on A. It would pretty much have routing information to B, C, and Other.

But a PC on A talking to another PC on A would not make use of routing.

There. I think I've even confused myself.

 

I'd add - for the vast majority of computers, the only route they need to know is the route to the default gateway. The default gateway is basically the most common pathway out of your network.

They need only ask one routing question - is the destination on my network. If yes, send comunication out to my network (either directly to the recipient or in the form of a broadcast); if no, send it to the default gateway to sort out.

I'd go further and say if basic client PCs on a network need any more routes than that to the default gateway, the person designing your network and/or configuring your routers, didn't do their job properly.

For people on small networks there is often only the network you are on and the internet. So the route out of your network is also the route to the internet.