DHCP an NAT

[Nathan Burgener]

Unfortunately I need the NAT.
So there is no possibility to configure the server, that it doesn't  
answer to 192.168.3.1 but on 172.18.1.1 ?

I have another idea. I can install the DHCP server in the same  
network, where the client is. But I must configure the server with  
special options, because the client will boot an image from the TFTP  
in network A.
I know, how I can configure the filename. But how can I configure,  
that the filename is not on the DHCP server, but on another server?


Am 15.07.2008 um 13:27 schrieb Simon Hobson:

>
> At 12:53 +0200 15/7/08, Nathan Burgener wrote:
>> Hello
>>
>> I have 2 networks, which are connected over a VPN. In the network  
>> A, there is a DHCP server.
>> In network B I have the client. But all client address from source  
>> 192.168.3.x get a IP from network 172.18.1.x with NAT and then the  
>> traffic goes through the VPN tunnel.
>> On the router in network B I have an ip helper-address to the DHCP  
>> server.
>>
>> Now the server gets the Discover from the client with the following  
>> informations:
>> Source IP 172.168.1.1
>> Destination: Address from DHCP server
>> Relay Agent IP Address: 192.168.3.1
>>
>> The DHCP server will now send back the offer. But the servers sends  
>> it to 192.168.3.1 and not to the address 172.168.1.1
>> How can I change that?
>
> Quick answer: Fix your network !
> NAT == broken<period> and DHCP will not work in this setup.
>
> You might be able to work around part of it by adding appropriate  
> routing and/or nat rules to get the packets back to the relay agent,  
> or by being creative with shared-network, but then the clients will  
> not be able to renew their leases later and things will still break.
>
> Can you remove the nat and make traffic routable between the server  
> subnet and the 192.163.3.x subnet ?
>
>