Hi, I'm experiencing issues with libvirt/kvm on Debian lenny. I have two servers (32 and amd64) with kvm and openvz and each time I start or destroy a kvm domain the network freeze during 20 or 30 seconds (even my openvz vms lost their network). I think it might come from the bridge config, but this is just a thought. Any help would be most welcome Some parameters : KVM Version: 72+dfsg-5~lenny4 qemu Version: 0.9.1-10lenny1 libvirt : Version: 0.7.6-1~bpo50+1 (vnet come from openvz) # brctl show bridge name bridge id STP enabled interfaces br0 8000.00fff11d455f no bond0 vnet0 vnet1 /etc/network/interface # The loopback network interface auto lo iface lo inet loopback # bond0 auto bond0 iface bond0 inet manual slaves eth0 eth1 metric 1 up ifconfig $IFACE 0.0.0.0 up || true # br0 auto br0 iface br0 inet static address 10.30.15.126 netmask 255.255.255.0 gateway 10.30.15.254 metric 0 bridge_ports bond0 Dmesg output [195651.085304] br0: port 2(vnet0) entering disabled state [195651.141339] device vnet0 left promiscuous mode [195651.141339] br0: port 2(vnet0) entering disabled state [197072.483514] kobject_add_internal failed for lo with -EEXIST, don't try to register things with the same name in the same directory. [197072.483608] Pid: 28725, comm: libvirtd Not tainted 2.6.26-2-openvz-amd64 #1 [197072.483651] [197072.483654] Call Trace: [197072.483741] [<ffffffff8030f8a9>] kobject_add_internal+0x13f/0x17e [197072.483791] [<ffffffff8030fce6>] kobject_add+0x74/0x7c [197072.483839] [<ffffffff8029bb16>] ____cache_alloc_node+0x6d/0x106 [197072.483897] [<ffffffff8029f3ac>] percpu_populate+0x77/0x9e [197072.483941] [<ffffffff8030e465>] __next_cpu+0x19/0x26 [197072.483981] [<ffffffff8030f700>] kobject_get+0x12/0x17 [197072.484024] [<ffffffff80377a8d>] get_device+0x17/0x1f [197072.484030] [<ffffffff803780ae>] device_add+0x9b/0x53f [197072.484030] [<ffffffff8030f4f2>] kobject_init_internal+0x12/0x2c [197072.484030] [<ffffffff803b1b5a>] register_netdevice+0x282/0x358 [197072.484030] [<ffffffff803b1c69>] register_netdev+0x39/0x46 [197072.484076] [<ffffffff8037e7c9>] loopback_net_init+0x3e/0x75 [197072.484076] [<ffffffff803ae23a>] setup_net+0x85/0xe6 [197072.484076] [<ffffffff803aea48>] copy_net_ns+0x49/0xb5 [197072.484076] [<ffffffff8024ad69>] create_new_namespaces+0x125/0x1da [197072.484076] [<ffffffff8024b012>] copy_namespaces+0x66/0x9c [197072.484076] [<ffffffff802336b8>] copy_process+0xa05/0x11fc [197072.484092] [<ffffffff80233fac>] do_fork_pid+0xfd/0x2aa [197072.484137] [<ffffffff80221f52>] do_page_fault+0x5c9/0x9ab [197072.484187] [<ffffffff802b1db5>] dput+0xc6/0x14f [197072.484242] [<ffffffff8020c00a>] system_call_after_swapgs+0x8a/0x8f [197072.484286] [<ffffffff8023416a>] do_fork+0x11/0x13 [197072.484325] [<ffffffff8020c397>] ptregscall_common+0x67/0xb0 [197072.484392] [199820.431786] device vnet0 entered promiscuous mode [199820.473424] br0: port 2(vnet0) entering learning state [199844.086318] vnet0: no IPv6 routers present [199857.512040] br0: topology change detected, propagating [199857.512075] br0: port 2(vnet0) entering forwarding state [201819.368519] device vnet1 entered promiscuous mode [201819.467978] br0: port 3(vnet1) entering learning state [201837.971816] vnet1: no IPv6 routers present [201843.849778] apic write: bad size=1 fee00030 [201843.849903] Ignoring de-assert INIT to vcpu 0 [201844.524922] Ignoring de-assert INIT to vcpu 0 [201846.852021] br0: topology change detected, propagating [201846.852065] br0: port 3(vnet1) entering forwarding state [202036.665085] br0: port 3(vnet1) entering disabled state [202038.731228] device vnet1 left promiscuous mode [202038.731272] br0: port 3(vnet1) entering disabled state [202066.345845] device vnet1 entered promiscuous mode [202066.565852] br0: port 3(vnet1) entering learning state [202070.052758] apic write: bad size=1 fee00030 [202070.052758] Ignoring de-assert INIT to vcpu 0 [202070.828029] Ignoring de-assert INIT to vcpu 0 [202088.866811] vnet1: no IPv6 routers present [202101.905984] br0: topology change detected, propagating [202101.906029] br0: port 3(vnet1) entering forwarding state [203602.877200] apic write: bad size=1 fee00030 [203602.877200] Ignoring de-assert INIT to vcpu 0 [203603.948087] Ignoring de-assert INIT to vcpu 0 [204019.458601] br0: port 2(vnet0) entering disabled state [204019.572050] device vnet0 left promiscuous mode [204019.572100] br0: port 2(vnet0) entering disabled state [207893.673407] device vnet0 entered promiscuous mode [207894.215321] br0: port 2(vnet0) entering learning state [207933.980412] vnet0: no IPv6 routers present [207946.360943] br0: topology change detected, propagating [207946.360990] br0: port 2(vnet0) entering forwarding state -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html