[Pkg-libvirt-maintainers] Bug#619929: Bug#619929: libvirt-bin: Error while attaching tap interface to bridge

[Guido Günther]

On Mon, Mar 28, 2011 at 07:18:32PM +0200, Guido Günther wrote:
> Hi,
> On Mon, Mar 28, 2011 at 03:21:01PM +0200, Loïc REVEST wrote:
> > Package: libvirt-bin
> > Version: 0.8.3-5+squeeze1
> > Severity: normal
> > 
> > 
> > I set up once a VM with Squeeze (using kvm) and a bridge (br0) with a "persistent" (added in /etc/network/interfaces) tap0 interface.
> > 
> > This VM worked perfectly with a command like "kvm -hda test.qcow2 [...] -net nic -net tap,ifname=tap0,script=no", guest was reachable through tap0
> > 
> > While I defined this VM through virsh (see dumpxml below), virsh get the VM started but couldn't ping it from host. VNC access worked, though (showing that VM was running indeed).
> > 
> > I got a "warning" in /var/log/messages :
> > 
> > libvirtd: 14:41:53.994: warning : qemudParsePCIDeviceStrs:1422 : Unexpected exit status '1', qemu probably failed
> > kernel: [136819.333361] device vnet0 entered promiscuous mode
> > kernel: [136819.333924] br0: topology change detected, propagating
> > kernel: [136819.333927] br0: port 2(vnet0) entering forwarding state
> > 
> > But nothing "suspect" in /var/log/libvirt/qemu/SqueezeVM.log :
> > 
> > LC_ALL=C PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin HOME=/root USER=root LOGNAME=root QEMU_AUDIO_DRV=none /usr/bin/kvm -S -M pc-0.12 -enable-kvm -m 1024 -smp 1,sockets=1,cores=1,threads=1 -name SqueezeVM -uuid a4c657ef-171b-7924-1f2b-629c4c0beda1 -nodefaults -chardev socket,id=monitor,path=/var/lib/libvirt/qemu/SqueezeVM.monitor,server,nowait -mon chardev=monitor,mode=readline -rtc base=utc -boot c -drive file=/home/loic/test.qcow2,if=none,id=drive-ide0-0-0,boot=on,format=raw -device ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -device rtl8139,vlan=0,id=net0,mac=52:54:00:19:d9:2e,bus=pci.0,addr=0x3 -net tap,fd=42,vlan=0,name=hostnet0 -usb -vnc 127.0.0.1:0 -vga std -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x4 -k fr
> > 
> > Running an "ifconfig" in VM shell, all I got was the "lo" interface.
> 
> Please check
> 
> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=593229
> 
> You might need to set clear_emulator_capabilities=0.

Rereading your configuration this shouldn't be necessary. This looks
more like a configuration error (like e.g. having a different mac now in
the guest so that udev renames the devices to eth1 (ifconfig -a)) than a
bug in libvirt. 

I just rechecked that adding tap devices to bridges works in
0.8.3-5+squeeze1.
 Cheers,
 -- Guido