After some digging in openvswitch code. My wild guess is that vlan tag reconfiguring triggered iface_configure_qos (vswitchd/bridge.c), which in turn called netdev_set_policing to reset ingress policing rate. Although there's no ingress_policing_rate set in my case, existing ingress qdisc still remove by default. Could some openvswitch guy help to confirm and suggest how to fix or workaround? It seems to be a bug of incompatible with existing ingress qdisc settings. Thanks, -- Qiu Yu On Wed, Jul 17, 2013 at 8:09 PM, Qiu Yu <unicell@xxxxxxxxx> wrote: > With outbound QoS setting in Libvirt XML, libvirt will add a tc > ingress qdisc for traffic shaping. Then if you set VLAN tag to that > tap device, this qdisc will automatically gone by no reason. > > Could anyone shed some lights where should I look into? I'm really > confused and got no clue here. Thanks! > > Steps to reproduce > -- > # virsh start instance-name > # virsh dumpxml instance-name > > ... > <interface type='bridge'> > <mac address='fa:16:3e:b9:8f:2a'/> > <source bridge='br-int'/> > <virtualport type='openvswitch'> > <parameters interfaceid='0a2b02ca-4824-4bda-baa9-05fff7a3146d'/> > </virtualport> > <target dev='tap0a2b02ca-48'/> > <model type='virtio'/> > <bandwidth> > <outbound average='256' peak='512' burst='512'/> > </bandwidth> > <alias name='net0'/> > <address type='pci' domain='0x0000' bus='0x00' slot='0x03' > function='0x0'/> > </interface> > ... > > # tc qdisc ls dev tap0a2b02ca-48 > qdisc htb 1: root refcnt 2 r2q 10 default 1 direct_packets_stat 0 > qdisc sfq 2: parent 1:1 limit 127p quantum 1514b perturb 10sec > qdisc ingress ffff: parent ffff:fff1 ---------------- (<-- already showed up) > > # ovs-vsctl set port tap0a2b02ca-48 tag=1 > # tc qdisc ls dev tap0a2b02ca-48 > qdisc htb 1: root refcnt 2 r2q 10 default 1 direct_packets_stat 0 > qdisc sfq 2: parent 1:1 limit 127p quantum 1514b perturb 10sec > (<-- ingress qdisc is gone) > > After that, if add this qdisc manually and re-set vlan tag, problem no > longer exists. But it can always be reproduced after "virsh destroy / > start" cycle. > > # tc qdisc add dev tap0a2b02ca-48 handle ffff: ingress > # ovs-vsctl clear port tap0a2b02ca-48 tag > # ovs-vsctl set port tap0a2b02ca-48 tag=1 > # tc qdisc ls dev tap0a2b02ca-48 > qdisc htb 1: root refcnt 2 r2q 10 default 1 direct_packets_stat 0 > qdisc sfq 2: parent 1:1 limit 127p quantum 1514b perturb 10sec > qdisc ingress ffff: parent ffff:fff1 ---------------- (<-- still exists) > > Other information > -- > # ovs-vsctl --version > ovs-vsctl (Open vSwitch) 1.9.2 > Compiled May 27 2013 14:19:16 > # uname -r > 2.6.32-358.111.1.openstack.el6.x86_64 > # virsh --version (This is a version I built from libvirt upstream > origin/v0.9.11-stable branch) > 0.9.11.9 > > -- > Qiu Yu _______________________________________________ libvirt-users mailing list libvirt-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvirt-users
