[Dnsmasq-discuss] Tagging DHCP request (network-id) by the incoming interface - possible?

[Daniel Lohmann]

Simon  wrote:

>> You might be able to keep the more traditional scheme with dnsmasq 
>> listening on the two interfaces without losing the bridge provided 
>> that you can divide your subnet into two.
>>
>> It's best to illustrate this with an example.
>>
>> Assume subnet is 192.168.1.xx (netmask 255.255.255.0)
>> and the bridge interface has address 192.168.1.10
>>
>> Now also configure the lan and wifi interfaces as
>>
>> 192.168.1.1/255.255.255.128 - lan
>> 192.168.1.129/255.255.255.128 - wifi
>>
>> you can now configure dnsmasq to do dhcp on those two interfaces with 
>> whatever policies you like, provided that lan clients are in the first 
>> half of the address range and wifi ones in the second.
>>
>> [...many more helpful explanations ...]
> 
> That sounds indeed like a possible solution! I will try it out as soon 
> as possible and post my results to the list.

Just to keep on the track for the archive:

Until now, I did not succeed. The reason seems to be a problem with the
OpenWRT firmware and or the fact that the lan interface is actually a
virtual interface.

The Asus WL-500 Deluxe uses a Broadcom 6-port switch which ports are
logically assigned to two virtual networks (one WAN port, four LAN ports
and one internal port for both) For details take a look at (link may wrap):

http://upload.wikimedia.org/wikipedia/commons/0/0f/WRT54G_internal_architecture.png 




The virtual lan network is represented by the interface vlan0. The
problem is that if I try to assign this interface a subnet mask that is
different from 255.255.255.0, the router freezes.

ifconfig vlan0 192.168.1.2 netmask 255.255.255.128

-> system hangs and does not anwser pings

(Note that I am connected via the wlan interface while doing this, so it
should not be the problem that I kick myself out of the net)


This is definitely not a dnsmasq related problem. I just want to mention
it here for the archives. I posted about the issue on the OpenWrt forum,
however, did not receive an anwser yet.


Daniel