DHCP restrictions

[paul000]

Hello friends ,

I want to ask you some about DHCP inside domain.
I want restrict to use DHCP for users and computers those not belong to w2k domain because at the moment if computer do not belong to domain he can receive IP from DHCP.

Thank you

 

[BigShyBear]

You can't restrict DHCP based on whether it belongs to the a domain or not. DHCP request and allocations occur much earlier in the bootup sequence for a computer, long before it knows anything about a domain.

 

[BigShyBear]

IF you want to do some work you can be sneaky. This will ONLY work in a small network, where you have some authority, and you can be a little nasty without getting fired.
1. Go through your network, find out all the computers getting an IP address from DHCP and get their MAC addresses.
2. Set up IP address reservations for all your computers based on the MAC addresses.
3. narrow the DHCP scope to EXACTLY the number of IP addresses you have allocated. (or better yet, set up exclusions so that the rest of IP addresses in your DHCP scope can't be assigned.)
4. Tell everybody that you have to see every computer that comes in before it goes onto the network. When they bring it in you get the MAC address, then set up an address reservation for this computer in your DHCP scope.

 

[GlenJohnson]

You can also put a hosts file on the machines you don't want to access the dhcp server with a dummy address so it can't talk to the dhcp server. The machines look at the hosts file on startup. If it has domain name wrong address, it won't find the dhcp server. Simple text file, no domain, no ip address. Good luck.

Glen A. Johnson
If you're from Northern Illinois/Southern Wisconsin feel free to join the Tek-Tips in Chicago, Illinois Forum.
TTinChicago
Johnson Computers

 

[Serbtastic]

DHCP requests use a broadcast, so a hosts file won't help you here.

 

[RobBentley]

If your not giving a client an IP address its effectivly not on the network. In that cause wouldn't something like MAC address filtering at router/switch level be better?

Robert Bentley

SynergyworksHosting.co.uk
"reliable services at realistic prices