Peter Stuge (stuge-vlan@xxxxxxx) wrote on 29 August 2006 04:41: >On Mon, Aug 28, 2006 at 10:35:38PM -0300, Carlos Carvalho wrote: >> I was looking at setup 1b at >> >> http://marc.theaimsgroup.com/?m=105098558615614 >> >> and have a question. How is the router told that packets to machine >> B must have tag 2, those to machine C must have tag 3, etc.? > >C is actually on VLAN 2 along with B, but I understand what you mean. Sure, sorry! >> Shouldn't there be a routing table somewhere? ... >The Linux bridging code works just like a regular L2 switch. (In >fact, L2 switches are precisely that: ethernet bridges.) To begin >with, it will broadcast packets but after some traffic has passed >in both directions it learns which machine is connected to which >port (VLAN interface) and after that it only sends traffic to >client box D on eth1.3, client box E on eth1.4 and so on. Thanks! If I had RTFM I'd have discovered it, sorry again... I implemented the 1b setup but have two problems. First, it doesn't work with the servers here because they have all MAC addresses configured statically and my machine couldn't find their MACs. Why putting static addresses on the *server* makes a *client* not find them? The switch also uses static addresses on the ports. I "solved" this putting the server address in the client directly. The second problem is a showstopper: dhcp doesn't work for some machines with bridging. Apparently it works for the machines that use the dhcp protocol but not for the ones that use bootp (!!??). I get a long series of BOOTREQUEST/BOOTREPLY in the server log but it seems the client doesn't get the answer. There are also some (rare) "ip length xxx disagrees with bytes received yyy" warnings. All eth0.xx interfaces use header reordering. Also, all traffic is tagged; eth0 itself doesn't have an IP. I have a working config that's identical to the bridging one (the vconfig commands are the same) but all eth0.xx have the same IP number and bridging is replaced by a routing table that points each IP to a vlan interface. This way dhcpd listens on all interfaces and there are no problems with bootp. The switch config is unchanged. Any ideas about why this happens?
