How can I block a computer from accessing the Internet?

[Doomer]

I've googled this till I'm blue in the face and cannot find an answer. I'll try to explain as simply as I can what I'm trying to do.

1. I want to block a computer from any and all access to the Internet.

2. I want to maintain said computer's local area connection unhindered.

3. I'd like to block the computer AND NOT the IP address. The network uses DHCP so ip's are subject to change so I assume that blocking by ip doesn't work very well.

4. I'm using Smoothwall Express 3.0.

The computer I want to block from the Internet is a headless WHS so if I goof it up and loose all connectivity, I'll be in deep doo doo.

TIA

 

[drebo]

Remove the default gateway from the computer's network configuration.

 

[mammador]

Your router admin page/site may have the ability to block communication to given MAC addresses. This would be better than an IP address, unless you've assigned it a static IP address.

 

[ch33zw1z]

Use Static DHCP and assign the PC's MAC an IP out of your DHCP range, then block the IP's internet access. That way you can leave DHCP enabled, but it's IP won't change.

 

[drebo]

It's a Windows Home Server...it's going to have a static IP anyway. Just don't input a gateway. Problem solved.

Way easier than mucking with anything on the router.

 

[ch33zw1z]

Just giving the guy options, drebo

http://www.smoothwall.org/images/promos/3.0/services-dhcp-proxy.png

 

[Doomer]

Thanks all. Leaving the gateway blank did the trick but the WHS was using DHCP so I gave it a static IP. I goofed and gave it the same IP as my NAS and thought I had lost it. in the panic that followed I realized what I did and temporarily shut down the NAS so I could get back into the WHS and correct my goof up.

 

[camoxiong]

use a software call network magic, it can let you kick out people as an intruder