DHCP an NAT

[Anton Lundin]

On 15 July, 2008 - Nathan Burgener wrote:

>
> 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?
>

Read up on the opts server-name next-server.

server-name is just the symbolic name of the server, and next-server is
what server to tftp from.

I have seen that not all pxe-roms i honer the next-server option...


//Anton



>
> 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 ?
>>
>>
>

-- 
Anton Lundin	+46702-161604
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 189 bytes
Desc: Digital signature
URL: <https://lists.isc.org/pipermail/dhcp-users/attachments/20080715/ad1ee1ca/attachment.bin>