[Bridge] Ubuntu: network bridging between wireless and wired connection fails

[Jochen Hebbrecht]

Nicolas de Pesloüan schreef:
> Jochen Hebbrecht a écrit :
>>
>>
>> Nicolas de Pesloüan schreef:
>>> Ok, now we understand what you are trying to do. In particular, I 
>>> assume the DHCP server is on the subnet of location B (or behind a 
>>> router connected on this subnet), so the expected DHCP offer will 
>>> come from the wire interface (eth0) and definitely not from the 
>>> wireless interface (eth1).
>>>
>> Maybe my picture isn't very clear, but my WAN access is on location 
>> A. There's a router which receives an ip from the ISP. On the other 
>> side, I'm having a 192.168.1.0/24 network
>
> I'm no more really sure I understand your configuration.
>
> The server you are curently trying to setup as a bridge is located in 
> location B (UBUNTU SERVER) and has two interfaces : eth0 (ethernet) 
> and eth1 (wifi).
>
> Am I right ?

Yes, that's totally correct. I want to receive an IP on my eth1 so my 
UBUNTU server is in the same subnet as desktop A and notebook A. By 
bridging eth0 and eth1 of UBUNTU SERVER, the IP packets on eth0 will be 
forwarded on eth1 to the router, so my printer can ask for a DHCP OFFER 
message, by sending a DHCP DISCOVER on the switch. That switch will send 
the message to eth0 of UBUNTU SERVER whichs forwards (bridging!) the 
packet on eth1 to the router. The router sends a DHCP OFFER back to eth1 
of UBUNTU SERVER, which eventually forwards (bridging!) the message back 
to switch (and so on to the printer :-))