[Babel-users] cornercase issue (link sensing)

[Harald Geyer]

> > - Especially vlan setups often use the same mac address on many
> > interfaces.
> 
> If there's a MAC address collision in a single broadcast domain,
> duplicate address detection at the IPv6 layer should disable one of the
> two interfaces.  (Or both, if there's a race condition.)

Well I plainly don't know if duplicate address detection always works 
reliably in wireless environments.

Just for the record: I got problems after doing some stupid
configuration error:
5: br0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue
    link/ether 00:16:01:8c:6f:c4 brd ff:ff:ff:ff:ff:ff
    inet 192.168.10.1/24 brd 192.168.10.255 scope global br0
    inet6 fe80::216:1ff:fe8c:6fc4/64 scope link
6: vlan0: <BROADCAST,MULTICAST,PROMISC,UP> mtu 1500 qdisc noqueue
    link/ether 00:16:01:8c:6f:c4 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::216:1ff:fe8c:6fc4/64 scope link

root at pioneer1:~# brctl show br0
bridge name     bridge id               STP enabled     interfaces
br0             8000.0016018c6fc4       no              vlan0

running babel on br0 and vlan0 had some very bad effects on the peer
nodes. Of course such a setup is completely broken. - I just wasn't
sure if something similiar could happen if you have vlan0 and 
vlan1 (and are forwarding both into the same wireless channel)...

I guess if in doubt, you need to carefully assign proper mac addresses.

Harald