[VLAN] broadcasts go where?

[Peter Stuge]

On Fri, May 19, 2006 at 03:05:39PM -0300, Carlos Carvalho wrote:
> I've grouped machines in the department in vlans, so they only
> communicate inside their group. We also have some servers which
> must be accessible by everyone, so I put them in all vlans. They
> have the same IP in all vlans.
> 
> Everything works fine except that broadcasts from the servers don't
> reach all machines, only those in the eth0 group, that is, the
> untagged vlan. So I ask if there's a way to make the server
> broadcast in all vlans.

I would suggest that you either use per-VLAN IP networks, or make a
bridge of all VLAN interfaces on the Linux system and use iptables to
control intra-VLAN-traffic.

Something like setup 1b perhaps:
http://marc.theaimsgroup.com/?m=105098558615614

To run dhcpd successfully (if you want to) you'll also need to do
vconfig set_flag eth1.2 1 1

for each VLAN interface included in the bridge.


//Peter