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DHCP Clients going to wrong DHCP servers 1

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DavePL

IS-IT--Management
Joined
Sep 11, 2000
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158
Location
US
We have a Novell network, and were assigning fixed IP addresses to clients. We recently installed DHCP service on an NT 4 server, and set the scope appropriately to our subnet. However the clients usually ignore our local DHCP server, and instead go through the gateway to another subnet, and obtain an address from that DHCP server.
So they get the wrong IP address from another subnet.
Conversely, some of the clients on the other subnet will go to our DHCP server and get one of our IP address!

When the clients run winipcfg and release and renew, they eventually get the right subnet, but that causes them to loose the Novell connection, and they have to re-log on.

Both our LANs use the same internet service provider, T1 line, and we both use the same DNS settings, for Domain and DNS server search order.

Our LANs are connected through cable modems. For gateways we use Baystack Advanced Remote Nodes.

We are wondering if there is a way we can make our clients only go to our DHCP server and not theirs.


 
When you place two DHCP servers on the same network you are going to have problems unless you have a router sitting between the two subnets, or you need to block broadcasts from crossing the subnets. DHCP clients broadcast for the DHCP server, the first one that answers the broadcast is the one responsible for assigning the IP address. I don't know too much about Gateways and don't know if you can block a broadcast through a Gateway (from my CCNA course I believe the answer is no). Once you block the broadcast from crosing the subnets you will be able to resolve your problem.
david e
*end users are just like computers, some you can work with...others just need a simple reBOOTing to fix their problems.*
 
How to find out if there is another DHCP server installed on the network with out the Administrators permtion.


kbaker
 
Usually (on CISCO anyway), you actually configure the DHCP/DNS details on the router. Maybe this needs to be changed to reflect your new DHCP server? Speak to your Network guys.
 
enable "LMHOSTS" in tcpip properties. Edit LMHOSTS
eg.

192.168.1.1 PDC #pre #dom:"your domain name"


The IP address will point the workstation to the preffered log on / DHCP server,
There is another way through the registry.
Another story.
 
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