[Qemu-devel] Qemu Multicast Bug??

[Andres E. Rodriguez Lazo]

Hello Qemu Developers.

Here at work we're implementing qemu
mcast networking while using avahi-autoipd to obtain network address.
The implementation of qemu networking is the following:

-net nic,vlan=1,macaddr=52:54:00:12:34:01,model=virtio -net socket,vlan=1,mcast=230.0.0.1:1234

So, while running avahi-autoipd we get his messages:

address@hidden ~]# avahi-autoipd eth1
Found user 'avahi-autoipd' (UID 499) and group 'avahi-autoipd' (GID 499).
Successfully called chroot().

Successfully dropped root privileges.
Starting with address 169.254.2.176
Callout BIND, address 169.254.2.176 on interface eth1
Received conflicting normal ARP packet.
Callout CONFLICT, address 169.254.2.176 on interface eth1
Trying address 169.254.189.32
Callout BIND, address 169.254.189.32 on interface eth1


Received conflicting normal ARP packet.

After
sniffing ARP packets, we've realized that we're getting ARP packets
back, which screws with autoipd. I think this is due to the mcast
implementation not doing RPF. Is your mcast implementation supposed to
do RPF?? If it is, we've got ourselves a bug.

Thanks for your help, 

Look forward to hear from you.

-- 
Andres E. Rodriguez Lazo (4nDr3s - RoAkSoAx)
Ubuntu Counter Project - User # 17582