[LARTC] Bridging three vlans

[Ed Wildgoose]

OK, strange request but I want to bridge three vlans under linux 2.4.  
Bridging works fine with two vlans, but is failing to route when I add 
the third vlan.

Situation is clearly to have Lan, internet and DMZ vlans.  The reason 
they are vlans is that I am using a Linksys WRT54GS and hence you 
effectively have a 5 port hub on the back which can be segregated into 
flexible vlan groups.  I clearly want to just be able to move something 
in and out of the DMZ depending on which port it's plugged into, but 
without having to change it's IP address or do any routing.  (I like 
transparent firewalls and QOS!)

So what's going wrong when I try to put my third vlan into the bridge?  
Actually it seems to be more fundamental than that.  The inet and lan 
vlans both have no IP address, can then build a bridge no problem.  As 
soon as I remove the ip address from the DMZ lan, even without adding it 
to the bridge, my routing stops working on the machine...

Is this a linux 2.4 limitation or user error?  Grateful for any advice

Thanks

Ed W