Re: [Qemu-devel] problems: running two instance of Qemu with same MAC address

[Rutger Nijlunsing <rutger@nospam.com>]

On Wed, May 19, 2004 at 03:32:44PM +0700, Mulyadi Santosa wrote:
> hello all
> 
> I have problem about identical MAC address...here is the scenario
> 
> I run two instances of Qemu for full system emulation. I use Qemu 0.5.5
> On both guest system, i can turn on the eth0 (NE 2000 card) . here is the 
> dmesg content:
> 
> On guest 1 and 2:
> NE*000 ethercard probe at 0x300: 52 54 00 12 34 56
> 
> Guest 1 IP on eth0 --> 192.168.1.21..attached to tun0 with IP -->192.168.1.11
> Guest 2 IP on eth0 --> 192.168.1.22..attached to tun0 with IP --> 192.168.1.12
> 
> here is the routing table at the host system:
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
> 192.168.1.21    *               255.255.255.255 UH        0 0          0 tun0
> 192.168.1.22    *               255.255.255.255 UH        0 0          0 tun1
> 10.1.1.0        *                    255.255.255.0   U         0 0     0 eth0
> 127.0.0.0       *               255.0.0.0       U         0 0          0 lo
> 
> Both guests can ping the host and the host can ping to these guests. When I 
> try to ping from  guest 1 to guest 2, it got no reply (i guess similar with 
> dropped packet when u do DROP with iptables)
> 
> I realize the fact that both eth0 on the guests when I do tcpdump-ing. Ping 
> from guest 1 yield arp broadcast, but never get arp-reply...So, what is the 
> workaround for this double MAC address problem?

You've got forwarding or bridging enabled in the host?

-- 
Rutger Nijlunsing ---------------------------- rutger ed tux tmfweb nl
never attribute to a conspiracy which can be explained by incompetence
----------------------------------------------------------------------