Port groups support

The Bare Metal service supports static configuration of port groups (bonds) in the instances via configdrive. See kernel documentation on bonding to see why it may be useful and how it is setup in linux. The sections below describe how to make use of them in the Bare Metal service.

Switch-side configuration

If port groups are desired in the ironic deployment, they need to be configured on the switches. It needs to be done manually, and the mode and properties configured on the switch have to correspond to the mode and properties that will be configured on the ironic side, as bonding mode and properties may be named differently on your switch, or have possible values different from the ones described in kernel documentation on bonding. Please refer to your switch configuration documentation for more details.

Provisioning and cleaning cannot make use of port groups if they need to boot the deployment ramdisk via (i)PXE. If your switches or desired port group configuration do not support port group fallback, which will allow port group members to be used by themselves, you need to set port group’s standalone_ports_supported value to be False in ironic, as it is True by default.

Physical networks

If any port in a port group has a physical network, then all ports in that port group must have the same physical network.

In order to change the physical network of the ports in a port group, all ports must first be removed from the port group, before changing their physical networks (to the same value), then adding them back to the port group.

See physical networks for further information on using physical networks in the Bare Metal service.

Port groups configuration in the Bare Metal service

Port group configuration is supported in ironic API microversions 1.26, the CLI commands below specify it for completeness.

  1. When creating a port group, the node to which it belongs must be specified, along with, optionally, its name, address, mode, properties, and if it supports fallback to standalone ports:

    baremetal port group create \
    --node $NODE_UUID --name test --address fa:ab:25:48:fd:ba --mode 802.3ad \
    --property miimon=100 --property xmit_hash_policy="layer2+3" \

    A port group can also be updated with baremetal port group set command, see its help for more details.

    If an address is not specified, the port group address on the deployed instance will be the same as the address of the neutron port that is attached to the port group. If the neutron port is not attached, the port group will not be configured.


    In standalone mode, port groups have to be configured manually. It can be done either statically inside the image, or by generating the configdrive and adding it to the node’s instance_info. For more information on how to configure bonding via configdrive, refer to cloud-init documentation and code. cloud-init version 0.7.7 or later is required for bonding configuration to work.

    The following is a simple sample for configuring bonding via configdrive:

    When booting an instance, it needs to add user-data file for configuring bonding via --user-data option. For example:

      "networks": [
          "type": "physical",
          "name": "eth0",
          "mac_address": "fa:ab:25:48:fd:ba"
          "type": "physical",
          "name": "eth1",
          "mac_address": "fa:ab:25:48:fd:ab"
          "type": "bond",
          "name": "bond0",
          "bond_interfaces": [
            "eth0", "eth1"
            "mode": "active-backup"

    If the port group’s address is not explicitly set in standalone mode, it will be set automatically by the process described in kernel documentation on bonding.

    During interface attachment, port groups have higher priority than ports, so they will be used first. (It is not yet possible to specify which one is desired, a port group or a port, in an interface attachment request). Port groups that don’t have any ports will be ignored.

    The mode and properties values are described in the kernel documentation on bonding. The default port group mode is active-backup, and this default can be changed by setting the [DEFAULT]default_portgroup_mode configuration option in the ironic API service configuration file.

  2. Associate ports with the created port group.

    It can be done on port creation:

    baremetal port create \
    --node $NODE_UUID --address fa:ab:25:48:fd:ba --port-group test

    Or by updating an existing port:

    baremetal port set $PORT_UUID --port-group $PORT_GROUP_UUID

    When updating a port, the node associated with the port has to be in enroll, manageable, or inspecting states. A port group can have the same or different address as individual ports.

  3. Boot an instance (or node directly, in case of using standalone ironic) providing an image that has cloud-init version 0.7.7 or later and supports bonding.

When the deployment is done, you can check that the port group is set up properly by running the following command in the instance:

cat /proc/net/bonding/bondX

where X is a number autogenerated by cloud-init for each configured port group, in no particular order. It starts with 0 and increments by 1 for every configured port group.