This section covers configuration of the Bifrost service that runs on the seed host. Bifrost configuration is typically applied in ${KAYOBE_CONFIG_PATH}/bifrost.yml. Consult the Bifrost documentation for further details of Bifrost usage and configuration.

Bifrost installation


This section may be skipped if using an upstream Bifrost container image.

The following options are used if building the Bifrost container image locally.


URL of Bifrost source code repository. Default is


Version (branch, tag, etc.) of Bifrost source code repository. Default is {{ openstack_branch }}, which is the same as the Kayobe upstream branch name.

For example, to install Bifrost from a custom git repository:

kolla_bifrost_source_version: downstream

Overcloud root disk image configuration

Bifrost uses Diskimage builder (DIB) to build a root disk image that is deployed to overcloud hosts when they are provisioned. The following options configure how this image is built. Consult the Diskimage-builder documentation for further information on building disk images.

The default configuration builds a CentOS 7 whole disk (partitioned) image with SELinux disabled and a serial console enabled. Cloud-init is used to process the configuration drive built by Bifrost, rather than the Bifrost default of simple-init.


DIB base OS element. Default is centos7.


DIB image OS release. Default is GenericCloud.


Added in the Train release. Use kolla_bifrost_dib_elements in earlier releases.

List of default DIB elements. Default is ["disable-selinux", "enable-serial-console", "vm"]. The vm element is poorly named, and causes DIB to build a whole disk image rather than a single partition.


Added in the Train release. Use kolla_bifrost_dib_elements in earlier releases.

List of additional DIB elements. Default is none.


List of DIB elements. Default is a combination of kolla_bifrost_dib_elements_default and kolla_bifrost_dib_elements_extra.


DIB init element. Default is cloud-init-datasources.


Added in the Train release. Use kolla_bifrost_dib_env_vars in earlier releases.

DIB default environment variables. Default is {"DIB_CLOUD_INIT_DATASOURCES": "ConfigDrive"}.


Added in the Train release. Use kolla_bifrost_dib_env_vars in earlier releases.

DIB additional environment variables. Default is none.


DIB environment variables. Default is combination of kolla_bifrost_dib_env_vars_default and kolla_bifrost_dib_env_vars_extra.


List of DIB packages to install. Default is to install no extra packages.

The disk image is built during the deployment of seed services. It is worth noting that currently, the image will not be rebuilt if it already exists. To force rebuilding the image, it is necessary to remove the file. On the seed:

docker exec bifrost_deploy rm /httpboot/deployment_image.qcow2

Then on the control host:

(kayobe) $ kayobe seed service deploy

Example: Adding an element

In the following, we extend the list of DIB elements to add the growpart element:

  - "growpart"

Example: Building an XFS root filesystem image

By default, DIB will format the image as ext4. In some cases it might be useful to use XFS, for example when using the overlay Docker storage driver which can reach the maximum number of hardlinks allowed by ext4.

In DIB, we achieve this by setting the FS_TYPE environment variable to xfs.

  FS_TYPE: "xfs"

In order to build the image, we also require the xfsprogs package to be installed in the Bifrost container. As of the Ussuri release of Bifrost this will be done automatically, but until then, the following workaround can be made on the seed host:

docker exec bifrost_deploy yum -y install xfsprogs

Example: Configuring a development user account


A development user account should not be used in production.

When debugging a failed deployment, it can sometimes be necessary to allow access to the image via a preconfigured user account with a known password. This can be achieved via the devuser element.

This example shows how to add the devuser element, and configure a username and password for an account that has passwordless sudo:

  - "devuser"

  DIB_DEV_USER_PASSWORD: "correct horse battery staple"

Alternatively, the dynamic-login element can be used to authorize SSH keys by appending them to the kernel arguments.

Example: Installing a package

It can be necessary to install additional packages in the root disk image. Rather than needing to write a custom DIB element, we can use the kolla_bifrost_dib_packages variable. For example, to install the biosdevname package:

  - "biosdevname"

Ironic configuration

The following options configure the Ironic service in the bifrost-deploy container.


List of hardware types to enable for Bifrost’s Ironic. Default is ["ipmi"].

Ironic Inspector configuration

The following options configure the Ironic Inspector service in the bifrost-deploy container.


List of of inspector processing plugins. Default is {{ inspector_processing_hooks }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


Which MAC addresses to add as ports during introspection. One of all, active or pxe. Default is {{ inspector_add_ports }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


List of extra kernel parameters for the inspector default PXE configuration. Default is {{ inspector_extra_kernel_options }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


List of introspection rules for Bifrost’s Ironic Inspector service. Default is {{ inspector_rules }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


Ironic inspector IPMI username to set via an introspection rule. Default is {{ ipmi_username }}, defined in ${KAYOBE_CONFIG_PATH}/bmc.yml.


Ironic inspector IPMI password to set via an introspection rule. Default is {{ ipmi_password }}, defined in ${KAYOBE_CONFIG_PATH}/bmc.yml.


Ironic inspector network interface name on which to check for an LLDP switch port description to use as the node’s name. Default is {{ inspector_lldp_switch_port_interface_default }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


Ironic inspector deployment kernel location. Default is http://{{ provision_oc_net_name | net_ip }}:8080/ipa.vmlinuz.


Ironic inspector deployment ramdisk location. Default is http://{{ provision_oc_net_name | net_ip }}:8080/ipa.initramfs.

Ironic Python Agent (IPA) configuration


If building IPA images locally (ipa_build_images is true) this section can be skipped.

The following options configure the source of Ironic Python Agent images used by Bifrost for inspection and deployment. Consult the Ironic Python Agent documentation for full details.


URL of Ironic Python Agent (IPA) kernel image. Default is {{ inspector_ipa_kernel_upstream_url }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


URL of checksum of Ironic Python Agent (IPA) kernel image. Default is {{ inspector_ipa_kernel_checksum_url }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


Algorithm of checksum of Ironic Python Agent (IPA) kernel image. Default is {{ inspector_ipa_kernel_checksum_algorithm }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


URL of Ironic Python Agent (IPA) ramdisk image. Default is {{ inspector_ipa_ramdisk_upstream_url }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


URL of checksum of Ironic Python Agent (IPA) ramdisk image. Default is {{ inspector_ipa_ramdisk_checksum_url }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.


Algorithm of checksum of Ironic Python Agent (IPA) ramdisk image. Default is {{ inspector_ipa_ramdisk_checksum_algorithm }}, defined in ${KAYOBE_CONFIG_PATH}/inspector.yml.

Inventory configuration


This feature is currently not well tested. It is advisable to use autodiscovery of overcloud servers instead.

The following options are used to configure a static inventory of servers for Bifrost.


Server inventory for Bifrost in the JSON file format.

Custom Configuration

Further configuration of arbitrary Ansible variables for Bifrost can be provided via the following files:

  • ${KAYOBE_CONFIG_PATH}/kolla/config/bifrost/bifrost.yml

  • ${KAYOBE_CONFIG_PATH}/kolla/config/bifrost/dib.yml

These are both passed as extra variables files to ansible-playbook, but the naming scheme provides a separation of DIB image related variables from other variables. It may be necessary to inspect the Bifrost source code for the full set of variables that may be configured.

For example, to configure debug logging for Ironic Inspector:

inspector_debug: true