7.5. Configure the Plug-in Agent

Configure the agent associated with the plug-in used in your environment. If you are using the ML2 plug-in or the Open vSwitch plug-in, configure the Open vSwitch agent. If you are using the Linux Bridge plug-in, configure the Linux Bridge agent.

7.5.1. Configure the Open vSwitch Plug-in Agent

You must install and enable the Open vSwitch plug-in before configuring it. See Section 7.2.1.2, “Enable the Open vSwitch Plug-in”.
The Open vSwitch plug-in has a corresponding agent. When the Open vSwitch plug-in is in use, all nodes in the environment that handle data packets must have the agent installed and configured. This includes all Compute nodes and systems hosting the dedicated DHCP and L3 agents.

Note

Open vSwitch support for TCP segmentation offload (TSO) and Generic Segmentation Offload (GSO) to VXLAN and GRE is enabled by default.

Procedure 7.14. Configuring the Open vSwitch Plug-in Agent

  1. Start the openvswitch service: 
    # systemctl start openvswitch.service
  2. Configure the openvswitch service to start at boot time: 
    # systemctl enable openvswitch.service
  3. Each host running the Open vSwitch agent requires an Open vSwitch bridge called br-int. This bridge is used for private network traffic: 
    # ovs-vsctl add-br br-int

    Warning

    The br-int bridge is required for the agent to function correctly. Once created, do not remove or otherwise modify the br-int bridge.
  4. Ensure that the br-int device persists on reboot by creating a /etc/sysconfig/network-scripts/ifcfg-br-int file, and adding the following lines: 
    DEVICE=br-int
DEVICETYPE=ovs
TYPE=OVSBridge
ONBOOT=yes
BOOTPROTO=none
  5. Set the value of the bridge_mappings configuration key to a comma-separated list of physical networks and the network bridges associated with them: 
    # openstack-config --set /etc/neutron/plugin.ini \
   OVS bridge_mappings PHYSNET:BRIDGE
    Replace PHYSNET with the name of a physical network, and replace BRIDGE with the name of the network bridge.
  6. Start the neutron-openvswitch-agent service: 
    # systemctl start neutron-openvswitch-agent.service
  7. Configure the neutron-openvswitch-agent service to start at boot time: 
    # systemctl enable neutron-openvswitch-agent.service
  8. Configure the neutron-ovs-cleanup service to start at boot time. This service ensures that the OpenStack Networking agents maintain full control over the creation and management of tap devices: 
    # systemctl enable neutron-ovs-cleanup.service

7.5.2. Configure the Linux Bridge Plug-in Agent

You must install and enable the Linux Bridge plug-in before configuring it. See Section 7.2.1.3, “Enable the Linux Bridge Plug-in”.
The Linux Bridge plug-in has a corresponding agent. When the Linux Bridge plug-in is in use, all nodes in the environment that handle data packets must have the agent installed and configured. This includes all Compute nodes and systems hosting the dedicated DHCP and L3 agents.

Procedure 7.15. Configuring the Linux Bridge Plug-in Agent

  1. Set the value of the physical_interface_mappings configuration key to a comma-separated list of physical networks and the VLAN ranges associated with them that are available for allocation to tenant networks: 
    # openstack-config --set /etc/neutron/plugin.ini \
   LINUX_BRIDGE physical_interface_mappings PHYSNET:VLAN_START:VLAN_END
    Replace the following values:
    • Replace PHYSNET with the name of a physical network.
    • Replace VLAN_START with an identifier indicating the start of the VLAN range.
    • Replace VLAN_END with an identifier indicating the end of the VLAN range.
  2. Start the neutron-linuxbridge-agent service: 
    # systemctl start neutron-linuxbridge-agent.service
  3. Configure the neutron-linuxbridge-agent service to start at boot time: 
    # systemctl enable neutron-linuxbridge-agent.service