Bug 2111015

In an ML2/OVS deployment, Open vSwitch (OVS) does not support offloading OpenFlow rules that have the `skb_priority`, `skb_mark`, or output queue fields set. Those fields are needed to provide quality-of-service (QoS) support for virtio ports. + If you set a minimum bandwidth rule for a virtio port, the Neutron Open vSwitch agent marks the traffic of this port with a Packet Mark Field. As a result, this traffic cannot be offloaded, and it affects the traffic in other ports. If you set a bandwidth limit rule, all traffic is marked with the default 0 queue, which means no traffic can be offloaded. + As a workaround, if your environment includes OVS hardware offload ports, disable the packet marking in the nodes that require hardware offloading. After you disable the packet marking, it will not be possible to set rate limiting rules for virtio ports. However, differentiated services code point (DSCP) marking rules will still be available. + In the configuration file, set the `disable_packet_marking` flag to `true`. After you edit the configuration file, you must restart the `neutron_ovs_agent` container. For example: + ---- $ cat `/var/lib/config-data/puppet-generated/neutron/etc/neutron/plugins/ml2/openvswitch_agent.ini` [ovs] disable_packet_marking=True ----