| ====================================== | 
 | Using DevStack with neutron Networking | 
 | ====================================== | 
 |  | 
 | This guide will walk you through using OpenStack neutron with the ML2 | 
 | plugin and the Open vSwitch mechanism driver. | 
 |  | 
 |  | 
 | .. _single-interface-ovs: | 
 |  | 
 | Using Neutron with a Single Interface | 
 | ===================================== | 
 |  | 
 | In some instances, like on a developer laptop, there is only one | 
 | network interface that is available. In this scenario, the physical | 
 | interface is added to the Open vSwitch bridge, and the IP address of | 
 | the laptop is migrated onto the bridge interface. That way, the | 
 | physical interface can be used to transmit self service project | 
 | network traffic, the OpenStack API traffic, and management traffic. | 
 |  | 
 |  | 
 | .. warning:: | 
 |  | 
 |     When using a single interface networking setup, there will be a | 
 |     temporary network outage as your IP address is moved from the | 
 |     physical NIC of your machine, to the OVS bridge. If you are SSH'd | 
 |     into the machine from another computer, there is a risk of being | 
 |     disconnected from your ssh session (due to arp cache | 
 |     invalidation), which would stop the stack.sh or leave it in an | 
 |     unfinished state. In these cases, start stack.sh inside its own | 
 |     screen session so it can continue to run. | 
 |  | 
 |  | 
 | Physical Network Setup | 
 | ---------------------- | 
 |  | 
 | In most cases where DevStack is being deployed with a single | 
 | interface, there is a hardware router that is being used for external | 
 | connectivity and DHCP. The developer machine is connected to this | 
 | network and is on a shared subnet with other machines.  The | 
 | `local.conf` exhibited here assumes that 1500 is a reasonable MTU to | 
 | use on that network. | 
 |  | 
 | .. nwdiag:: | 
 |  | 
 |         nwdiag { | 
 |                 inet [ shape = cloud ]; | 
 |                 router; | 
 |                 inet -- router; | 
 |  | 
 |                 network hardware_network { | 
 |                         address = "172.18.161.0/24" | 
 |                         router [ address = "172.18.161.1" ]; | 
 |                         devstack-1 [ address = "172.18.161.6" ]; | 
 |                 } | 
 |         } | 
 |  | 
 |  | 
 | DevStack Configuration | 
 | ---------------------- | 
 |  | 
 | The following is a complete `local.conf` for the host named | 
 | `devstack-1`. It will run all the API and services, as well as | 
 | serving as a hypervisor for guest instances. | 
 |  | 
 | :: | 
 |  | 
 |         [[local|localrc]] | 
 |         HOST_IP=172.18.161.6 | 
 |         SERVICE_HOST=172.18.161.6 | 
 |         MYSQL_HOST=172.18.161.6 | 
 |         RABBIT_HOST=172.18.161.6 | 
 |         GLANCE_HOSTPORT=172.18.161.6:9292 | 
 |         ADMIN_PASSWORD=secret | 
 |         DATABASE_PASSWORD=secret | 
 |         RABBIT_PASSWORD=secret | 
 |         SERVICE_PASSWORD=secret | 
 |  | 
 |         ## Neutron options | 
 |         Q_USE_SECGROUP=True | 
 |         FLOATING_RANGE="172.18.161.0/24" | 
 |         FIXED_RANGE="10.0.0.0/24" | 
 |         Q_FLOATING_ALLOCATION_POOL=start=172.18.161.250,end=172.18.161.254 | 
 |         PUBLIC_NETWORK_GATEWAY="172.18.161.1" | 
 |         PUBLIC_INTERFACE=eth0 | 
 |  | 
 |         # Open vSwitch provider networking configuration | 
 |         Q_USE_PROVIDERNET_FOR_PUBLIC=True | 
 |         OVS_PHYSICAL_BRIDGE=br-ex | 
 |         PUBLIC_BRIDGE=br-ex | 
 |         OVS_BRIDGE_MAPPINGS=public:br-ex | 
 |  | 
 |  | 
 | Adding Additional Compute Nodes | 
 | ------------------------------- | 
 |  | 
 | Let's suppose that after installing DevStack on the first host, you | 
 | also want to do multinode testing and networking. | 
 |  | 
 | Physical Network Setup | 
 | ~~~~~~~~~~~~~~~~~~~~~~ | 
 |  | 
 | .. nwdiag:: | 
 |  | 
 |         nwdiag { | 
 |                 inet [ shape = cloud ]; | 
 |                 router; | 
 |                 inet -- router; | 
 |  | 
 |                 network hardware_network { | 
 |                         address = "172.18.161.0/24" | 
 |                         router [ address = "172.18.161.1" ]; | 
 |                         devstack-1 [ address = "172.18.161.6" ]; | 
 |                         devstack-2 [ address = "172.18.161.7" ]; | 
 |                 } | 
 |         } | 
 |  | 
 |  | 
 | After DevStack installs and configures Neutron, traffic from guest VMs | 
 | flows out of `devstack-2` (the compute node) and is encapsulated in a | 
 | VXLAN tunnel back to `devstack-1` (the control node) where the L3 | 
 | agent is running. | 
 |  | 
 | :: | 
 |  | 
 |     stack@devstack-2:~/devstack$ sudo ovs-vsctl show | 
 |     8992d965-0ba0-42fd-90e9-20ecc528bc29 | 
 |         Bridge br-int | 
 |             fail_mode: secure | 
 |             Port br-int | 
 |                 Interface br-int | 
 |                     type: internal | 
 |             Port patch-tun | 
 |                 Interface patch-tun | 
 |                     type: patch | 
 |                     options: {peer=patch-int} | 
 |         Bridge br-tun | 
 |             fail_mode: secure | 
 |             Port "vxlan-c0a801f6" | 
 |                 Interface "vxlan-c0a801f6" | 
 |                     type: vxlan | 
 |                     options: {df_default="true", in_key=flow, local_ip="172.18.161.7", out_key=flow, remote_ip="172.18.161.6"} | 
 |             Port patch-int | 
 |                 Interface patch-int | 
 |                     type: patch | 
 |                     options: {peer=patch-tun} | 
 |             Port br-tun | 
 |                 Interface br-tun | 
 |                     type: internal | 
 |         ovs_version: "2.0.2" | 
 |  | 
 | Open vSwitch on the control node, where the L3 agent runs, is | 
 | configured to de-encapsulate traffic from compute nodes, then forward | 
 | it over the `br-ex` bridge, where `eth0` is attached. | 
 |  | 
 | :: | 
 |  | 
 |     stack@devstack-1:~/devstack$ sudo ovs-vsctl show | 
 |     422adeea-48d1-4a1f-98b1-8e7239077964 | 
 |         Bridge br-tun | 
 |             fail_mode: secure | 
 |             Port br-tun | 
 |                 Interface br-tun | 
 |                     type: internal | 
 |             Port patch-int | 
 |                 Interface patch-int | 
 |                     type: patch | 
 |                     options: {peer=patch-tun} | 
 |             Port "vxlan-c0a801d8" | 
 |                 Interface "vxlan-c0a801d8" | 
 |                     type: vxlan | 
 |                     options: {df_default="true", in_key=flow, local_ip="172.18.161.6", out_key=flow, remote_ip="172.18.161.7"} | 
 |         Bridge br-ex | 
 |             Port phy-br-ex | 
 |                 Interface phy-br-ex | 
 |                     type: patch | 
 |                     options: {peer=int-br-ex} | 
 |             Port "eth0" | 
 |                 Interface "eth0" | 
 |             Port br-ex | 
 |                 Interface br-ex | 
 |                     type: internal | 
 |         Bridge br-int | 
 |             fail_mode: secure | 
 |             Port "tapce66332d-ea" | 
 |                 tag: 1 | 
 |                 Interface "tapce66332d-ea" | 
 |                     type: internal | 
 |             Port "qg-65e5a4b9-15" | 
 |                 tag: 2 | 
 |                 Interface "qg-65e5a4b9-15" | 
 |                     type: internal | 
 |             Port "qr-33e5e471-88" | 
 |                 tag: 1 | 
 |                 Interface "qr-33e5e471-88" | 
 |                     type: internal | 
 |             Port "qr-acbe9951-70" | 
 |                 tag: 1 | 
 |                 Interface "qr-acbe9951-70" | 
 |                     type: internal | 
 |             Port br-int | 
 |                 Interface br-int | 
 |                     type: internal | 
 |             Port patch-tun | 
 |                 Interface patch-tun | 
 |                     type: patch | 
 |                     options: {peer=patch-int} | 
 |             Port int-br-ex | 
 |                 Interface int-br-ex | 
 |                     type: patch | 
 |                     options: {peer=phy-br-ex} | 
 |         ovs_version: "2.0.2" | 
 |  | 
 | `br-int` is a bridge that the Open vSwitch mechanism driver creates, | 
 | which is used as the "integration bridge" where ports are created, and | 
 | plugged into the virtual switching fabric. `br-ex` is an OVS bridge | 
 | that is used to connect physical ports (like `eth0`), so that floating | 
 | IP traffic for project networks can be received from the physical | 
 | network infrastructure (and the internet), and routed to self service | 
 | project network ports.  `br-tun` is a tunnel bridge that is used to | 
 | connect OpenStack nodes (like `devstack-2`) together. This bridge is | 
 | used so that project network traffic, using the VXLAN tunneling | 
 | protocol, flows between each compute node where project instances run. | 
 |  | 
 |  | 
 |  | 
 | DevStack Compute Configuration | 
 | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | 
 |  | 
 | The host `devstack-2` has a very minimal `local.conf`. | 
 |  | 
 | :: | 
 |  | 
 |     [[local|localrc]] | 
 |     HOST_IP=172.18.161.7 | 
 |     SERVICE_HOST=172.18.161.6 | 
 |     MYSQL_HOST=172.18.161.6 | 
 |     RABBIT_HOST=172.18.161.6 | 
 |     GLANCE_HOSTPORT=172.18.161.6:9292 | 
 |     ADMIN_PASSWORD=secret | 
 |     MYSQL_PASSWORD=secret | 
 |     RABBIT_PASSWORD=secret | 
 |     SERVICE_PASSWORD=secret | 
 |  | 
 |     ## Neutron options | 
 |     PUBLIC_INTERFACE=eth0 | 
 |     ENABLED_SERVICES=n-cpu,rabbit,q-agt | 
 |  | 
 | Network traffic from `eth0` on the compute nodes is then NAT'd by the | 
 | controller node that runs Neutron's `neutron-l3-agent` and provides L3 | 
 | connectivity. | 
 |  | 
 |  | 
 | Neutron Networking with Open vSwitch and Provider Networks | 
 | ========================================================== | 
 |  | 
 | In some instances, it is desirable to use neutron's provider | 
 | networking extension, so that networks that are configured on an | 
 | external router can be utilized by neutron, and instances created via | 
 | Nova can attach to the network managed by the external router. | 
 |  | 
 | For example, in some lab environments, a hardware router has been | 
 | pre-configured by another party, and an OpenStack developer has been | 
 | given a VLAN tag and IP address range, so that instances created via | 
 | DevStack will use the external router for L3 connectivity, as opposed | 
 | to the neutron L3 service. | 
 |  | 
 | Physical Network Setup | 
 | ---------------------- | 
 |  | 
 | .. nwdiag:: | 
 |  | 
 |         nwdiag { | 
 |                 inet [ shape = cloud ]; | 
 |                 router; | 
 |                 inet -- router; | 
 |  | 
 |                 network provider_net { | 
 |                         address = "203.0.113.0/24" | 
 |                         router [ address = "203.0.113.1" ]; | 
 |                         controller; | 
 |                         compute1; | 
 |                         compute2; | 
 |                 } | 
 |  | 
 |                 network control_plane { | 
 |                         router [ address = "10.0.0.1" ] | 
 |                         address = "10.0.0.0/24" | 
 |                         controller [ address = "10.0.0.2" ] | 
 |                         compute1 [ address = "10.0.0.3" ] | 
 |                         compute2 [ address = "10.0.0.4" ] | 
 |                 } | 
 |         } | 
 |  | 
 |  | 
 | On a compute node, the first interface, eth0 is used for the OpenStack | 
 | management (API, message bus, etc) as well as for ssh for an | 
 | administrator to access the machine. | 
 |  | 
 | :: | 
 |  | 
 |         stack@compute:~$ ifconfig eth0 | 
 |         eth0      Link encap:Ethernet  HWaddr bc:16:65:20:af:fc | 
 |                   inet addr:10.0.0.3 | 
 |  | 
 | eth1 is manually configured at boot to not have an IP address. | 
 | Consult your operating system documentation for the appropriate | 
 | technique. For Ubuntu, the contents of `/etc/network/interfaces` | 
 | contains: | 
 |  | 
 | :: | 
 |  | 
 |         auto eth1 | 
 |         iface eth1 inet manual | 
 |                 up ifconfig $IFACE 0.0.0.0 up | 
 |                 down ifconfig $IFACE 0.0.0.0 down | 
 |  | 
 | The second physical interface, eth1 is added to a bridge (in this case | 
 | named br-ex), which is used to forward network traffic from guest VMs. | 
 |  | 
 | :: | 
 |  | 
 |         stack@compute:~$ sudo ovs-vsctl add-br br-ex | 
 |         stack@compute:~$ sudo ovs-vsctl add-port br-ex eth1 | 
 |         stack@compute:~$ sudo ovs-vsctl show | 
 |         9a25c837-32ab-45f6-b9f2-1dd888abcf0f | 
 |             Bridge br-ex | 
 |                 Port br-ex | 
 |                     Interface br-ex | 
 |                         type: internal | 
 |                 Port phy-br-ex | 
 |                     Interface phy-br-ex | 
 |                         type: patch | 
 |                         options: {peer=int-br-ex} | 
 |                 Port "eth1" | 
 |                     Interface "eth1" | 
 |  | 
 |  | 
 | Service Configuration | 
 | --------------------- | 
 |  | 
 | **Control Node** | 
 |  | 
 | In this example, the control node will run the majority of the | 
 | OpenStack API and management services (keystone, glance, | 
 | nova, neutron) | 
 |  | 
 |  | 
 | **Compute Nodes** | 
 |  | 
 | In this example, the nodes that will host guest instances will run | 
 | the ``neutron-openvswitch-agent`` for network connectivity, as well as | 
 | the compute service ``nova-compute``. | 
 |  | 
 | DevStack Configuration | 
 | ---------------------- | 
 |  | 
 | .. _ovs-provider-network-controller: | 
 |  | 
 | The following is a snippet of the DevStack configuration on the | 
 | controller node. | 
 |  | 
 | :: | 
 |  | 
 |         HOST_IP=10.0.0.2 | 
 |         SERVICE_HOST=10.0.0.2 | 
 |         MYSQL_HOST=10.0.0.2 | 
 |         RABBIT_HOST=10.0.0.2 | 
 |         GLANCE_HOSTPORT=10.0.0.2:9292 | 
 |         PUBLIC_INTERFACE=eth1 | 
 |  | 
 |         ADMIN_PASSWORD=secret | 
 |         MYSQL_PASSWORD=secret | 
 |         RABBIT_PASSWORD=secret | 
 |         SERVICE_PASSWORD=secret | 
 |  | 
 |         ## Neutron options | 
 |         Q_USE_SECGROUP=True | 
 |         ENABLE_PROJECT_VLANS=True | 
 |         PROJECT_VLAN_RANGE=3001:4000 | 
 |         PHYSICAL_NETWORK=default | 
 |         OVS_PHYSICAL_BRIDGE=br-ex | 
 |  | 
 |         Q_USE_PROVIDER_NETWORKING=True | 
 |  | 
 |         disable_service q-l3 | 
 |  | 
 |         ## Neutron Networking options used to create Neutron Subnets | 
 |  | 
 |         FIXED_RANGE="203.0.113.0/24" | 
 |         NETWORK_GATEWAY=203.0.113.1 | 
 |         PROVIDER_SUBNET_NAME="provider_net" | 
 |         PROVIDER_NETWORK_TYPE="vlan" | 
 |         SEGMENTATION_ID=2010 | 
 |         USE_SUBNETPOOL=False | 
 |  | 
 | In this configuration we are defining FIXED_RANGE to be a | 
 | publicly routed IPv4 subnet. In this specific instance we are using | 
 | the special TEST-NET-3 subnet defined in `RFC 5737 <http://tools.ietf.org/html/rfc5737>`_, | 
 | which is used for documentation.  In your DevStack setup, FIXED_RANGE | 
 | would be a public IP address range that you or your organization has | 
 | allocated to you, so that you could access your instances from the | 
 | public internet. | 
 |  | 
 | The following is the DevStack configuration on | 
 | compute node 1. | 
 |  | 
 | :: | 
 |  | 
 |         HOST_IP=10.0.0.3 | 
 |         SERVICE_HOST=10.0.0.2 | 
 |         MYSQL_HOST=10.0.0.2 | 
 |         RABBIT_HOST=10.0.0.2 | 
 |         GLANCE_HOSTPORT=10.0.0.2:9292 | 
 |         ADMIN_PASSWORD=secret | 
 |         MYSQL_PASSWORD=secret | 
 |         RABBIT_PASSWORD=secret | 
 |         SERVICE_PASSWORD=secret | 
 |  | 
 |         # Services that a compute node runs | 
 |         ENABLED_SERVICES=n-cpu,rabbit,q-agt | 
 |  | 
 |         ## Open vSwitch provider networking options | 
 |         PHYSICAL_NETWORK=default | 
 |         OVS_PHYSICAL_BRIDGE=br-ex | 
 |         PUBLIC_INTERFACE=eth1 | 
 |         Q_USE_PROVIDER_NETWORKING=True | 
 |  | 
 | Compute node 2's configuration will be exactly the same, except | 
 | ``HOST_IP`` will be ``10.0.0.4`` | 
 |  | 
 | When DevStack is configured to use provider networking (via | 
 | ``Q_USE_PROVIDER_NETWORKING`` is True) - | 
 | DevStack will automatically add the network interface defined in | 
 | ``PUBLIC_INTERFACE`` to the ``OVS_PHYSICAL_BRIDGE`` | 
 |  | 
 | For example, with the above  configuration, a bridge is | 
 | created, named ``br-ex`` which is managed by Open vSwitch, and the | 
 | second interface on the compute node, ``eth1`` is attached to the | 
 | bridge, to forward traffic sent by guest VMs. | 
 |  | 
 | Miscellaneous Tips | 
 | ================== | 
 |  | 
 | Non-Standard MTU on the Physical Network | 
 | ---------------------------------------- | 
 |  | 
 | Neutron by default uses a MTU of 1500 bytes, which is | 
 | the standard MTU for Ethernet. | 
 |  | 
 | A different MTU can be specified by adding the following to | 
 | the Neutron section of `local.conf`. For example, | 
 | if you have network equipment that supports jumbo frames, you could | 
 | set the MTU to 9000 bytes by adding the following | 
 |  | 
 | :: | 
 |  | 
 |     [[post-config|/$Q_PLUGIN_CONF_FILE]] | 
 |     global_physnet_mtu = 9000 | 
 |  | 
 |  | 
 | Disabling Next Generation Firewall Tools | 
 | ---------------------------------------- | 
 |  | 
 | DevStack does not properly operate with modern firewall tools.  Specifically | 
 | it will appear as if the guest VM can access the external network via ICMP, | 
 | but UDP and TCP packets will not be delivered to the guest VM.  The root cause | 
 | of the issue is that both ufw (Uncomplicated Firewall) and firewalld (Fedora's | 
 | firewall manager) apply firewall rules to all interfaces in the system, rather | 
 | then per-device.  One solution to this problem is to revert to iptables | 
 | functionality. | 
 |  | 
 | To get a functional firewall configuration for Fedora do the following: | 
 |  | 
 | :: | 
 |  | 
 |          sudo service iptables save | 
 |          sudo systemctl disable firewalld | 
 |          sudo systemctl enable iptables | 
 |          sudo systemctl stop firewalld | 
 |          sudo systemctl start iptables | 
 |  | 
 |  | 
 | To get a functional firewall configuration for distributions containing ufw, | 
 | disable ufw.  Note ufw is generally not enabled by default in Ubuntu.  To | 
 | disable ufw if it was enabled, do the following: | 
 |  | 
 | :: | 
 |  | 
 |         sudo service iptables save | 
 |         sudo ufw disable | 
 |  | 
 | Configuring Extension Drivers for the ML2 Plugin | 
 | ------------------------------------------------ | 
 |  | 
 | Extension drivers for the ML2 plugin are set with the variable | 
 | ``Q_ML2_PLUGIN_EXT_DRIVERS``, and includes the 'port_security' extension | 
 | by default. If you want to remove all the extension drivers (even | 
 | 'port_security'), set ``Q_ML2_PLUGIN_EXT_DRIVERS`` to blank. | 
 |  | 
 |  | 
 | Using Linux Bridge instead of Open vSwitch | 
 | ------------------------------------------ | 
 |  | 
 | The configuration for using the Linux Bridge ML2 driver is fairly | 
 | straight forward. The Linux Bridge configuration for DevStack is similar | 
 | to the :ref:`Open vSwitch based single interface <single-interface-ovs>` | 
 | setup, with small modifications for the interface mappings. | 
 |  | 
 |  | 
 | :: | 
 |  | 
 |     [[local|localrc]] | 
 |     HOST_IP=172.18.161.6 | 
 |     SERVICE_HOST=172.18.161.6 | 
 |     MYSQL_HOST=172.18.161.6 | 
 |     RABBIT_HOST=172.18.161.6 | 
 |     GLANCE_HOSTPORT=172.18.161.6:9292 | 
 |     ADMIN_PASSWORD=secret | 
 |     DATABASE_PASSWORD=secret | 
 |     RABBIT_PASSWORD=secret | 
 |     SERVICE_PASSWORD=secret | 
 |  | 
 |     ## Neutron options | 
 |     Q_USE_SECGROUP=True | 
 |     FLOATING_RANGE="172.18.161.0/24" | 
 |     FIXED_RANGE="10.0.0.0/24" | 
 |     Q_FLOATING_ALLOCATION_POOL=start=172.18.161.250,end=172.18.161.254 | 
 |     PUBLIC_NETWORK_GATEWAY="172.18.161.1" | 
 |     PUBLIC_INTERFACE=eth0 | 
 |  | 
 |     Q_USE_PROVIDERNET_FOR_PUBLIC=True | 
 |  | 
 |     # Linuxbridge Settings | 
 |     Q_AGENT=linuxbridge | 
 |     LB_PHYSICAL_INTERFACE=eth0 | 
 |     PUBLIC_PHYSICAL_NETWORK=default | 
 |     LB_INTERFACE_MAPPINGS=default:eth0 | 
 |  | 
 | Using MacVTap instead of Open vSwitch | 
 | ------------------------------------------ | 
 |  | 
 | Security groups are not supported by the MacVTap agent. Due to that, devstack | 
 | configures the NoopFirewall driver on the compute node. | 
 |  | 
 | MacVTap agent does not support l3, dhcp and metadata agent. Due to that you can | 
 | chose between the following deployment scenarios: | 
 |  | 
 | Single node with provider networks using config drive and external l3, dhcp | 
 | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | 
 | This scenario applies, if l3 and dhcp services are provided externally, or if | 
 | you do not require them. | 
 |  | 
 |  | 
 | :: | 
 |  | 
 |     [[local|localrc]] | 
 |     HOST_IP=10.0.0.2 | 
 |     SERVICE_HOST=10.0.0.2 | 
 |     MYSQL_HOST=10.0.0.2 | 
 |     RABBIT_HOST=10.0.0.2 | 
 |     ADMIN_PASSWORD=secret | 
 |     MYSQL_PASSWORD=secret | 
 |     RABBIT_PASSWORD=secret | 
 |     SERVICE_PASSWORD=secret | 
 |  | 
 |     Q_ML2_PLUGIN_MECHANISM_DRIVERS=macvtap | 
 |     Q_USE_PROVIDER_NETWORKING=True | 
 |  | 
 |     enable_plugin neutron git://git.openstack.org/openstack/neutron | 
 |  | 
 |     ## MacVTap agent options | 
 |     Q_AGENT=macvtap | 
 |     PHYSICAL_NETWORK=default | 
 |  | 
 |     FIXED_RANGE="203.0.113.0/24" | 
 |     NETWORK_GATEWAY=203.0.113.1 | 
 |     PROVIDER_SUBNET_NAME="provider_net" | 
 |     PROVIDER_NETWORK_TYPE="vlan" | 
 |     SEGMENTATION_ID=2010 | 
 |     USE_SUBNETPOOL=False | 
 |  | 
 |     [[post-config|/$Q_PLUGIN_CONF_FILE]] | 
 |     [macvtap] | 
 |     physical_interface_mappings = $PHYSICAL_NETWORK:eth1 | 
 |  | 
 |     [[post-config|$NOVA_CONF]] | 
 |     force_config_drive = True | 
 |  | 
 |  | 
 | Multi node with MacVTap compute node | 
 | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | 
 | This scenario applies, if you require OpenStack provided l3, dhcp or metadata | 
 | services. Those are hosted on a separate controller and network node, running | 
 | some other l2 agent technology (in this example Open vSwitch). This node needs | 
 | to be configured for VLAN tenant networks. | 
 |  | 
 | For OVS, a similar configuration like described in the | 
 | :ref:`OVS Provider Network <ovs-provider-network-controller>` section can be | 
 | used. Just add the following line to this local.conf, which also loads | 
 | the MacVTap mechanism driver: | 
 |  | 
 | :: | 
 |  | 
 |     [[local|localrc]] | 
 |     ... | 
 |     Q_ML2_PLUGIN_MECHANISM_DRIVERS=openvswitch,linuxbridge,macvtap | 
 |     ... | 
 |  | 
 | For the MacVTap compute node, use this local.conf: | 
 |  | 
 | :: | 
 |  | 
 |     HOST_IP=10.0.0.3 | 
 |     SERVICE_HOST=10.0.0.2 | 
 |     MYSQL_HOST=10.0.0.2 | 
 |     RABBIT_HOST=10.0.0.2 | 
 |     ADMIN_PASSWORD=secret | 
 |     MYSQL_PASSWORD=secret | 
 |     RABBIT_PASSWORD=secret | 
 |     SERVICE_PASSWORD=secret | 
 |  | 
 |     # Services that a compute node runs | 
 |     disable_all_services | 
 |     enable_plugin neutron git://git.openstack.org/openstack/neutron | 
 |     ENABLED_SERVICES+=n-cpu,q-agt | 
 |  | 
 |     ## MacVTap agent options | 
 |     Q_AGENT=macvtap | 
 |     PHYSICAL_NETWORK=default | 
 |  | 
 |     [[post-config|/$Q_PLUGIN_CONF_FILE]] | 
 |     [macvtap] | 
 |     physical_interface_mappings = $PHYSICAL_NETWORK:eth1 |