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vasan

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Linux Networking question

I have an NT4.0 server to which the @Home cable network is connected. My LAN (5 PCs-Win95) get on the Internet via the MS Proxy server in the NT Server. Now I want to add a Linux box to the LAN. Though the Linux box can see the NT server, it sees nothing beyond. Besides making Linux the server, is there any other way?
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vasan

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Edited text of question
You basically have a routing problem.  NT needs to be told to serve as an IP router between your lan (including the Linux box) and the @home network.  Not having NT4.0, I can't give you exact steps, but it basically amounts to this:

- Configure NT so it can use @home - you've already done this
- Make sure all machines can see the NT server -- done
- Now the tricky parts:  

     First, I'll assume @Home has assigned your machines a given address range - not a single address.  If you have to make all your machines perform on that single address, this isn't routing, this is IP Masquerading.  Windows NT doesn't support this.
If you have multiple IP addresses assigned from @Home for each of your workstations, then we proceed with a routing issue.  I'll assume this is so.

- Assume that @Home has assigned your machines, including the NT box, addresses 10.0.0.1 through 10.0.0.6 for your six fictionaly machines.  (Obviously, 10.0.0.0 and 10.0.0.7 are broadcast and your netmask (255.255.255.248) filters them out anyway.

On the NT box, you need to run what ever router software NT includes to perform RIP style routing.  In linux, its' routed.  In addition, make sure NT server has kernel routing enabled.  Without this, the packets on either end will hit the server and stop.

- Last, point all machines default gateway routes to the NT server and point the NT server default gateway to the @Home bridge.
Avatar of vasan

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@Home gives you only one IP address. If I had a range of IPs from them, this question would be moot. I just connect the cable modem to a hub, andall machines would route to the Internet!!
Then what you ask about is not IP routing but masquerading.  Windows NT can't do this.  Linux can however, but you'll need a younger kernel to do it.
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I am sorry if I was not clear. My NT server has MS Proxy installed on it, which in essence does IP masquerading. This is how the IPs of my Win95 machines get through. Their IPs are translated to the one IP of @Home. For some reason the Proxy server is not translating the IP of the LInux box.
What's the Linux box's default gateway set to?  It should be the NT box if that is exactly where the cable modem is.

Also, when you say your Win95 boxes get out on the Internet, you mean that you can telnet anywhere on the internet, or do you mean that you can use Netscape/IExplorer to get anywhere?  In the latter, you set the proxy server that you wish to go through, so naturally you'll get where you want, but in the former, you need a gateway setup....
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All my Win95 workstations use the non-routable IP range of 192.168.0.0.  The gateway in each of those machines is 192.168.0.10 which happens to be the IP of one of the NICs in my NT box. The second NIC in my NT has the Cable IP assigned to me by @home.
When I say all my Win95 machines route to the Internet, I mean I can Telnet, FTP, WWW, Email, everything. The only thing I can't do is, Ping or Traceroute. This is because NT does'nt route ICMP packets. That's fine.
The gateway in the Linux box is also 192.168.0.10
Not sure I understand what you mean by a non-routable IP range, but this is a weird one....  Can you use Netscape to get out on the Internet on the Linux box using your NT box in the Proxy configuration?

Stupid question too - you can telnet and ftp to the NT box from the Linux box, right?  Netmasks checked?

You may want to check to make sure that NT's routing configuration for any options that could relate.  Unfortunately, I don't have a reference guide yet (just switched jobs), but there may be some switches that will help you out.

Also, did you activate IP-Forwarding.  I think it is in the Network Control Panel somewhere.  
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There are some IP address ranges which do not route on the Internet. One such is the 192.168.0.0
Anyone can use this within a LAN. Everything on the NT including IP forwarding is activated. I have no problem connecting to any site anywhere in the World, from any of my Win95 workstations.
From the Linux box, I can ping the NT server, but can't go out to the Internet.
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I'll try this and let you know
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I tried this, and it works. Thanks.